JScript Run-Time Library Reference

Microsoft Office JScript

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Microsoft® JScript® JScript Language Reference  JScript Tutorial 
 Version Information 


 Feature Information

 Alphabetic Keyword List

 Errors

 Functions

 Methods

 Objects

 Operators

 Properties

 Statements
 

Welcome to the JScript Language Reference

These handy blocks of information will help you explore the many different parts of JScript.

You'll find all the parts of the JScript language listed alphabetically under the Alphabetic Keyword List. But if you want to examine just one category, say, objects, each language category has its own, more compact section.

How's it work? Click on one of the headings to the left to display a list of items contained in that category. From this list, select the topic that you want to view. Once you've opened that topic, you can easily link to other related sections.

So, go ahead and take a look! Study some statements, mull over the methods, or figure out a few functions. You'll see just how versatile the JScript language can be!

 

Features
 Description
Version Information
 List of JScript versions by host application and list of features by version.
JScript Features (ECMA)
 List of ECMA features currently in JScript.
JScript Features (Non-ECMA)
 List of non-ECMA features currently in JScript.
Microsoft Scripting Run-time Features
 List of scripting run-time features currently in JScript.
Language Element
 Description
$1...$9 Properties Returns the nine most-recently memorized portions found during pattern matching.
abs Method Returns the absolute value of a number.
acos Method Returns the arccosine of a number.
ActiveXObject Object Enables and returns a reference to an Automation object.
Addition Operator (+) Sums two numbers or concatenates two strings.
anchor Method Places an HTML anchor with a NAME attribute around specified text in the object.
arguments Property Returns an array containing each argument passed to the currently executing function.
Array Object Provides support for creation of arrays of any data type.
asin Method Returns the arcsine of a number.
Assignment Operator (=) Assigns a value to a variable.
atan Method Returns the arctangent of a number.
atan2 Method Returns the angle (in radians) from the X axis to a point (y,x).
atEnd Method Returns a Boolean value indicating if the enumerator is at the end of the collection.
big Method Places HTML <BIG> tags around text in a String object.
Bitwise AND Operator (&) Performs a bitwise AND on two expressions.
Bitwise Left Shift Operator (<<) Shifts the bits of an expression to the left.
Bitwise NOT Operator (~) Performs a bitwise NOT (negation) on an expression.
Bitwise OR Operator (|) Performs a bitwise OR on two expressions.
Bitwise Right Shift Operator (>>) Shifts the bits of an expression to the right, maintaining sign.
Bitwise XOR Operator (^) Performs a bitwise exclusive OR on two expressions.
blink Method Places HTML <BLINK> tags around text in a String object.
bold Method Places HTML <B> tags around text in a String object.
Boolean Object Creates a new Boolean value.
break Statement Terminates the current loop, or if in conjunction with a label, terminates the associated statement.
caller Property Returns a reference to the function that invoked the current function.
catch Statement Contains statements to execute when an error occurs in code within the try block.
@cc_on Statement Activates conditional compilation support.
ceil Method Returns the smallest integer greater than or equal to its numeric argument.
charAt Method Returns the character at the specified index.
charCodeAt Method Returns the Unicode encoding of the specified character.
Comma Operator (,) Causes two expressions to be executed sequentially.
// (Single-line Comment Statement) Causes single-line comments to be ignored by the JScript parser.
/*..*/ (Multiline Comment Statement) Causes multiline comments to be ignored by the JScript parser.
Comparison Operators Returns a Boolean value indicating the result of the comparison.
compile Method Compiles a regular expression into an internal format.
Compound Assignment Operators List of compound assignment operators.
concat Method (Array) Returns a new array consisting of a combination of two arrays.
concat Method (String) Returns a String object containing the concatenation of two supplied strings.
Conditional Compilation Allows the use of new JScript language features without sacrificing compatibility with browsers that don't support the features.
Conditional Compilation Variables List of predefined variables used with conditional compilation.
Conditional (trinary) Operator (?:) Executes one of two expressions depending on a condition.
constructor Property Specifies the function that creates an object.
continue Statement Stops the current iteration of a loop, and starts a new iteration.
cos Method Returns the cosine of a number.
Data Type Conversion Description of automatic data type conversion in JScript.
Date Object Enables basic storage and retrieval of dates and times.
Decrement Operator (--) Decrements a variable by one.
delete Operator Deletes a property from an object, or removes an element from an array.
description Property Returns or sets the descriptive string associated with a specific error.
Dictionary Object Object that stores data key, item pairs.
dimensions Method Returns the number of dimensions in a VBArray.
Division Operator (/) Divides two numbers and returns a numeric result.
do...while Statement Executes a statement block once, and then repeats execution of the loop until a condition expression evaluates to false.
E Property Returns Euler's constant, the base of natural logarithms.
Enumerator Object Enables enumeration of items in a collection.
Equality Operator (==) Compares two expressions to determine if they are equal.
Error Object An object that contains information about errors that occur while JScript code is running.
escape Method Encodes String objects so they can be read on all computers.
eval Method Evaluates JScript code and executes it.
exec Method Executes a search for a match in a specified string.
exp Method Returns e (the base of natural logarithms) raised to a power.
FileSystemObject Object Provides access to a computer's file system.
fixed Method Places HTML <TT> tags around text in a String object.
floor Method Returns the greatest integer less than or equal to its numeric argument.
fontcolor Method Places an HTML <FONT> tag with the COLOR attribute around the text in a String object.
fontsize Method Places an HTML <FONT> tag with the SIZE attribute around the text in a String object.
for Statement Executes a block of statements for as long as a specified condition is true.
for...in Statement Executes one or more statements for each element of an object or array.
fromCharCode Method Returns a string from a number of Unicode character values.
Function Object Creates a new function.
function Statement Declares a new function.
getDate Method Returns the day of the month value in a Date object using local time.
getDay Method Returns the day of the week value in a Date object using local time.
getFullYear Method Returns the year value in the Date object using local time.
getHours Method Returns the hours value in a Date object using local time.
getItem Method Returns the item at the specified location.
getMilliseconds Method Returns the milliseconds value in a Date object using local time.
getMinutes Method Returns the minutes value stored in a Date object using local time.
getMonth Method Returns the month value in the Date object using local time.
GetObject Function Returns a reference to an Automation object from a file.
getSeconds Method Returns seconds value stored in a Date object using local time.
getTime Method Returns the time value in a Date object.
getTimezoneOffset Method Returns the difference in minutes between the time on the host computer and Universal Coordinated Time (UTC).
getUTCDate Method Returns the date value in a Date object using Universal Coordinated Time (UTC).
getUTCDay Method Returns the day of the week value in a Date object using Universal Coordinated Time (UTC).
getUTCFullYear Method Returns the year value in a Date object using Universal Coordinated Time (UTC).
getUTCHours Method Returns the hours value in a Date object using Universal Coordinated Time (UTC).
getUTCMilliseconds Method Returns the milliseconds value in a Date object using Universal Coordinated Time (UTC).
getUTCMinutes Method Returns the minutes value in a Date object using Universal Coordinated Time (UTC).
getUTCMonth Method Returns the month value in a Date object using Universal Coordinated Time (UTC).
getUTCSeconds Method Returns the seconds value in a Date object using Universal Coordinated Time (UTC).
getVarDate Method Returns the VT_DATE value in a Date object.
getYear Method Returns the year value in a Date object.
Global Object An intrinsic object whose purpose is to collect global methods into one object.
Greater than Operator (>) Compares two expressions to determine if one is greater than the other.
Greater than or equal to Operator (>=) Compares two expressions to determine if one is greater than or equal to the other.
Identity Operator (===) Compares two expressions to determine if they are equal in value and of the same data type.
@if Statement Conditionally executes a group of statements, depending on the value of an expression.
if...else Statement Conditionally executes a group of statements, depending on the value of an expression.
Increment Operator (++) Increments a variable by one.
index Property Returns the character position where the first successful match begins in a searched string.
indexOf Method Returns the character position where the first occurrence of a substring occurs within a String object.
Inequality Operator (!=) Compares two expressions to determine if they are unequal.
Infinity Property Returns an initial value of Number.POSITIVE_INFINITY.
input Property Returns the string against which a search was performed.
instanceof Operator Returns a Boolean value that indicates whether or not an object is an instance of a particular class.
isFinite Method Returns a Boolean value that indicates if a supplied number is finite.
isNaN Method Returns a Boolean value that indicates whether a value is the reserved value NaN (not a number).
italics Method Places HTML <I> tags around text in a String object.
item Method Returns the current item in the collection.
join Method Returns a String object consisting of all the elements of an array concatenated together.
Labeled Statement Provides an identifier for a statement.
lastIndex Property Returns the character position where the last successful match begins in a searched string.
lastIndexOf Method Returns the last occurrence of a substring within a String object.
lbound Method Returns the lowest index value used in the specified dimension of a VBArray.
length Property (Array) Returns an integer value one higher than the highest element defined in an array.
length Property (Function) Returns the number of arguments defined for a function.
length Property (String) Returns the length of a String object.
Less than Operator (<) Compares two expressions to determine if one is less than the other.
Less than or equal to Operator (<=) Compares two expressions to determine if one is less than or equal to the other.
link Method Places an HTML anchor with an HREF attribute around the text in a String object.
LN2 Property Returns the natural logarithm of 2.
LN10 Property Returns the natural logarithm of 10.
log Method Returns the natural logarithm of a number.
LOG2E Property Returns the base-2 logarithm of e, Euler's constant.
LOG10E Property Returns the base-10 logarithm of e, Euler's constant.
Logical AND Operator (&&) Performs a logical conjunction on two expressions.
Logical NOT Operator (!) Performs logical negation on an expression.
Logical OR Operator (||) Performs a logical disjunction on two expressions.
match Method Returns, as an array, the results of a search on a string using a supplied Regular Expression object.
Math Object A intrinsic object that provides basic mathematics functionality and constants.
max Method Returns the greater of two supplied numeric expressions.
MAX_VALUE Property Returns the largest number that can be represented in JScript.
min Method Returns the lesser of two supplied numbers.
MIN_VALUE Property Returns the number closest to zero that can be represented in JScript.
Modulus Operator (%) Divides two numbers and returns the remainder.
moveFirst Method Resets the current item in the collection to the first item.
moveNext Method Moves the current item to the next item in the collection.
Multiplication Operator (*) Multiplies two numbers.
NaN Property (Global) Returns the special value NaN indicating that an expression is not a number.
NaN Property (Number) Returns the special value (NaN) indicating that an expression is not a number.
NEGATIVE_INFINITY Property Returns a value more negative than the largest negative number (-Number.MAX_VALUE) that can be represented in JScript.
new Operator Creates a new object.
Nonidentity Operator (!==) Compares two expressions to determine if they are not equal in value or of the same data type.
Number Object An object representation of the number data type and placeholder for numeric constants.
number Property Returns or sets the numeric value associated with a specific error.
Object Object Provides functionality common to all JScript objects.
Operator Precedence List containing information about the execution precedence of JScript operators.
parse Method Parses a string containing a date, and returns the number of milliseconds between that date and midnight, January 1, 1970.
parseFloat Method Returns a floating-point number converted from a string.
parseInt Method Returns an integer converted from a string.
PI Property Returns the ratio of the circumference of a circle to its diameter, approximately 3.141592653589793.
POSITIVE_INFINITY Property Returns a value larger than the largest number (Number.MAX_VALUE) that can be represented in JScript.
pow Method Returns the value of a base expression raised to a specified power.
prototype Property Returns a reference to the prototype for a class of objects.
random Method Returns a pseudorandom number between 0 and 1.
RegExp Object Stores information on regular expression pattern searches.
Regular Expression Object Contains a regular expression pattern.
Regular Expression Syntax A list of the special characters and sequences used in writing patterns for regular expressions.
replace Method Returns a copy of a string with text replaced using a regular expression.
return Statement Exits from the current function and returns a value from that function.
reverse Method Returns an Array object with the elements reversed.
round Method Returns a specified numeric expression rounded to the nearest integer.
Run-time Errors List of JScript run-time errors.
ScriptEngine Function Returns a string representing the scripting language in use.
ScriptEngineBuildVersion Function Returns the build version number of the scripting engine in use.
ScriptEngineMajorVersion Function Returns the major version number of the scripting engine in use.
ScriptEngineMinorVersion Function Returns the minor version number of the scripting engine in use.
search Method Returns the position of the first substring match in a regular expression search.
@set Statement Creates variables used with conditional compilation statements.
setDate Method Sets the numeric date of the Date object using local time.
setFullYear Method Sets the year value in the Date object using local time.
setHours Method Sets the hour value in the Date object using local time.
setMilliseconds Method Sets the milliseconds value in the Date object using local time.
setMinutes Method Sets the minutes value in the Date object using local time.
setMonth Method Sets the month value in the Date object using local time.
setSeconds Method Sets the seconds value in the Date object using local time.
setTime Method Sets the date and time value in the Date object.
setUTCDate Method Sets the numeric date in the Date object using Universal Coordinated Time (UTC).
setUTCFullYear Method Sets the year value in the Date object using Universal Coordinated Time (UTC).
setUTCHours Method Sets the hours value in the Date object using Universal Coordinated Time (UTC).
setUTCMilliseconds Method Sets the milliseconds value in the Date object using Universal Coordinated Time (UTC).
setUTCMinutes Method Sets the minutes value in the Date object using Universal Coordinated Time (UTC).
setUTCMonth Method Sets the month value in the Date object using Universal Coordinated Time (UTC).
setUTCSeconds Method Sets the seconds value in the Date object using Universal Coordinated Time (UTC).
setYear Method Sets the year value in the Date object.
sin Method Returns the sine of a number.
slice Method (Array) Returns a section of an array.
slice Method (String) Returns a section of a string.
small Method Places HTML <SMALL> tags around text in a String object.
sort Method Returns an Array object with the elements sorted.
source Property Returns a copy of the text of the regular expression pattern.
split Method Returns the array of strings that results when a string is separated into substrings.
sqrt Method Returns the square root of a number.
SQRT1_2 Property Returns the square root of 0.5, or one divided by the square root of 2.
SQRT2 Property Returns the square root of 2.
strike Method Places HTML <STRIKE> tags around text in a String object.
String Object Allows manipulation and formatting of text strings and determination and location of substrings within strings.
sub Method Places HTML <SUB;> tags around text in a String object.
substr Method Returns a substring beginning at a specified location and having a specified length.
substring Method Returns the substring at a specified location within a String object.
Subtraction Operator (-) Performs subtraction of two expressions.
sup Method Places HTML <SUP> tags around text in a String object.
switch Statement Enables the execution of one or more statements when a specified expression's value matches a label.
Syntax Errors List of JScript run-time errors.
tan Method Returns the tangent of a number.
test Method Returns a Boolean value that indicates whether or not a pattern exists in a searched string.
this Statement Refers to the current object.
throw Statement Generates an error condition that can be handled by a try...catch statement.
toArray Method Returns a standard JScript array converted from a VBArray.
toGMTString Method Returns a date converted to a string using Greenwich Mean Time (GMT).
toLocaleString Method Returns a date converted to a string using the current locale.
toLowerCase Method Returns a string where all alphabetic characters have been converted to lowercase.
toString Method Returns a string representation of an object.
toUpperCase Method Returns a string where all alphabetic characters have been converted to uppercase.
toUTCString Method Returns a date converted to a string using Universal Coordinated Time (UTC).
try Statement Implements error handling for JScript.
typeof Operator Returns a string that identifies the data type of an expression.
ubound Method Returns the highest index value used in the specified dimension of the VBArray.
Unary Negation Operator (-) Indicates the negative value of a numeric expression.
unescape Method Decodes String objects encoded with the escape method.
Unsigned Right Shift Operator (>>>) Performs an unsigned right shift of the bits in an expression.
UTC Method Returns the number of milliseconds between midnight, January 1, 1970 Universal Coordinated Time (UTC) (or GMT) and the supplied date.
valueOf Method Returns the primitive value of the specified object.
var Statement Declares a variable.
VBArray Object Provides access to Visual Basic safe arrays.
void Operator Prevents an expression from returning a value.
while Statement Executes a statement until a specified condition is false.
with Statement Establishes the default object for a statement.
Language Element
 Description
GetObject Function Returns a reference to an Automation object from a file.
ScriptEngine Function Returns a string representing the scripting language in use.
ScriptEngineBuildVersion Function Returns the build version number of the scripting engine in use.
ScriptEngineMajorVersion Function Returns the major version number of the scripting engine in use.
ScriptEngineMinorVersion Function Returns the minor version number of the scripting engine in use.
Language Element
 Description
abs Method Returns the absolute value of a number.
acos Method Returns the arccosine of a number.
anchor Method Places an HTML anchor with a NAME attribute around specified text in the object.
asin Method Returns the arcsine of a number.
atan Method Returns the arctangent of a number.
atan2 Method Returns the angle (in radians) from the X axis to a point (y,x).
atEnd Method Returns a Boolean value indicating if the enumerator is at the end of the collection.
big Method Places HTML <BIG> tags around text in a String object.
blink Method Places HTML <BLINK> tags around text in a String object.
bold Method Places HTML <B> tags around text in a String object.
ceil Method Returns the smallest integer greater than or equal to its numeric argument.
charAt Method Returns the character at the specified index.
charCodeAt Method Returns the Unicode encoding of the specified character.
compile Method Compiles a regular expression into an internal format.
concat Method (Array) Returns a new array consisting of a combination of two arrays.
concat Method (String) Returns a String object containing the concatenation of two supplied strings.
cos Method Returns the cosine of a number.
dimensions Method Returns the number of dimensions in a VBArray.
escape Method Encodes String objects so they can be read on all computers.
eval Method Evaluates JScript code and executes it.
exec Method Executes a search for a match in a specified string.
exp Method Returns e (the base of natural logarithms) raised to a power.
fixed Method Places HTML <TT> tags around text in a String object.
floor Method Returns the greatest integer less than or equal to its numeric argument.
fontcolor Method Places an HTML <FONT> tag with the COLOR attribute around the text in a String object.
fontsize Method Places an HTML <FONT> tag with the SIZE attribute around the text in a String object.
fromCharCode Method Returns a string from a number of Unicode character values.
getDate Method Returns the day of the month value in a Date object using local time.
getDay Method Returns the day of the week value in a Date object using local time.
getFullYear Method Returns the year value in the Date object using local time.
getHours Method Returns the hours value in a Date object using local time.
getItem Method Returns the item at the specified location.
getMilliseconds Method Returns the milliseconds value in a Date object using local time.
getMinutes Method Returns the minutes value stored in a Date object using local time.
getMonth Method Returns the month value in the Date object using local time.
getSeconds Method Returns seconds value stored in a Date object using local time.
getTime Method Returns the time value in a Date object.
getTimezoneOffset Method Returns the difference in minutes between the time on the host computer and Universal Coordinated Time (UTC).
getUTCDate Method Returns the date value in a Date object using Universal Coordinated Time (UTC).
getUTCDay Method Returns the day of the week value in a Date object using Universal Coordinated Time (UTC).
getUTCFullYear Method Returns the year value in a Date object using Universal Coordinated Time (UTC).
getUTCHours Method Returns the hours value in a Date object using Universal Coordinated Time (UTC).
getUTCMilliseconds Method Returns the milliseconds value in a Date object using Universal Coordinated Time (UTC).
getUTCMinutes Method Returns the minutes value in a Date object using Universal Coordinated Time (UTC).
getUTCMonth Method Returns the month value in a Date object using Universal Coordinated Time (UTC).
getUTCSeconds Method Returns the seconds value in a Date object using Universal Coordinated Time (UTC).
getVarDate Method Returns the VT_DATE value in a Date object.
getYear Method Returns the year value in a Date object.
indexOf Method Returns the character position where the first occurrence of a substring occurs within a String object.
isFinite Method Returns a Boolean value that indicates if a supplied number is finite.
isNaN Method Returns a Boolean value that indicates whether a value is the reserved value NaN (not a number).
italics Method Places HTML <I> tags around text in a String object.
item Method Returns the current item in the collection.
join Method Returns a String object consisting of all the elements of an array concatenated together.
lastIndexOf Method Returns the last occurrence of a substring within a String object.
lbound Method Returns the lowest index value used in the specified dimension of a VBArray.
link Method Places an HTML anchor with an HREF attribute around the text in a String object.
log Method Returns the natural logarithm of a number.
match Method Returns, as an array, the results of a search on a string using a supplied Regular Expression object.
max Method Returns the greater of two supplied numeric expressions.
min Method Returns the lesser of two supplied numbers.
moveFirst Method Resets the current item in the collection to the first item.
moveNext Method Moves the current item to the next item in the collection.
parse Method Parses a string containing a date, and returns the number of milliseconds between that date and midnight, January 1, 1970.
parseFloat Method Returns a floating-point number converted from a string.
parseInt Method Returns an integer converted from a string.
pow Method Returns the value of a base expression raised to a specified power.
random Method Returns a pseudorandom number between 0 and 1.
replace Method Returns a copy of a string with text replaced using a regular expression.
reverse Method Returns an Array object with the elements reversed.
round Method Returns a specified numeric expression rounded to the nearest integer.
search Method Returns the position of the first substring match in a regular expression search.
setDate Method Sets the numeric date of the Date object using local time.
setFullYear Method Sets the year value in the Date object using local time.
setHours Method Sets the hour value in the Date object using local time.
setMilliseconds Method Sets the milliseconds value in the Date object using local time.
setMinutes Method Sets the minutes value in the Date object using local time.
setMonth Method Sets the month value in the Date object using local time.
setSeconds Method Sets the seconds value in the Date object using local time.
setTime Method Sets the date and time value in the Date object.
setUTCDate Method Sets the numeric date in the Date object using Universal Coordinated Time (UTC).
setUTCFullYear Method Sets the year value in the Date object using Universal Coordinated Time (UTC).
setUTCHours Method Sets the hours value in the Date object using Universal Coordinated Time (UTC).
setUTCMilliseconds Method Sets the milliseconds value in the Date object using Universal Coordinated Time (UTC).
setUTCMinutes Method Sets the minutes value in the Date object using Universal Coordinated Time (UTC).
setUTCMonth Method Sets the month value in the Date object using Universal Coordinated Time (UTC).
setUTCSeconds Method Sets the seconds value in the Date object using Universal Coordinated Time (UTC).
setYear Method Sets the year value in the Date object.
sin Method Returns the sine of a number.
slice Method (Array) Returns a section of an array.
slice Method (String) Returns a section of a string.
small Method Places HTML <SMALL> tags around text in a String object.
sort Method Returns an Array object with the elements sorted.
split Method Returns the array of strings that results when a string is separated into substrings.
sqrt Method Returns the square root of a number.
strike Method Places HTML <STRIKE> tags around text in a String object.
sub Method Places HTML <SUB;> tags around text in a String object.
substr Method Returns a substring beginning at a specified location and having a specified length.
substring Method Returns the substring at a specified location within a String object.
sup Method Places HTML <SUP> tags around text in a String object.
tan Method Returns the tangent of a number.
test Method Returns a Boolean value that indicates whether or not a pattern exists in a searched string.
toArray Method Returns a standard JScript array converted from a VBArray.
toGMTString Method Returns a date converted to a string using Greenwich Mean Time (GMT).
toLocaleString Method Returns a date converted to a string using the current locale.
toLowerCase Method Returns a string where all alphabetic characters have been converted to lowercase.
toString Method Returns a string representation of an object.
toUpperCase Method Returns a string where all alphabetic characters have been converted to uppercase.
toUTCString Method Returns a date converted to a string using Universal Coordinated Time (UTC).
ubound Method Returns the highest index value used in the specified dimension of the VBArray.
unescape Method Decodes String objects encoded with the escape method.
UTC Method Returns the number of milliseconds between midnight, January 1, 1970 Universal Coordinated Time (UTC) (or GMT) and the supplied date.
valueOf Method Returns the primitive value of the specified object.
Language Element
 Description
ActiveXObject Object Enables and returns a reference to an Automation object.
Array Object Provides support for creation of arrays of any data type.
Boolean Object Creates a new Boolean value.
Date Object Enables basic storage and retrieval of dates and times.
Dictionary Object Object that stores data key, item pairs.
Enumerator Object Enables enumeration of items in a collection.
Error Object An object that contains information about errors that occur while JScript code is running.
FileSystemObject Object Provides access to a computer's file system.
Function Object Creates a new function.
Global Object An intrinsic object whose purpose is to collect global methods into one object.
Math Object A intrinsic object that provides basic mathematics functionality and constants.
Number Object An object representation of the number data type and placeholder for numeric constants.
Object Object Provides functionality common to all JScript objects.
RegExp Object Stores information on regular expression pattern searches.
Regular Expression Object Contains a regular expression pattern.
String Object Allows manipulation and formatting of text strings and determination and location of substrings within strings.
VBArray Object Provides access to Visual Basic safe arrays.
Language Element
 Description
Addition Operator (+) Sums two numbers or concatenates two strings.
Assignment Operator (=) Assigns a value to a variable.
Bitwise AND Operator (&) Performs a bitwise AND on two expressions.
Bitwise Left Shift Operator (<<) Shifts the bits of an expression to the left.
Bitwise NOT Operator (~) Performs a bitwise NOT (negation) on an expression.
Bitwise OR Operator (|) Performs a bitwise OR on two expressions.
Bitwise Right Shift Operator (>>) Shifts the bits of an expression to the right, maintaining sign.
Bitwise XOR Operator (^) Performs a bitwise exclusive OR on two expressions.
Comma Operator (,) Causes two expressions to be executed sequentially.
Comparison Operators Returns a Boolean value indicating the result of the comparison.
Compound Assignment Operators List of compound assignment operators.
Conditional (trinary) Operator (?:) Executes one of two expressions depending on a condition.
Decrement Operator (--) Decrements a variable by one.
delete Operator Deletes a property from an object, or removes an element from an array.
Division Operator (/) Divides two numbers and returns a numeric result.
Equality Operator (==) Compares two expressions to determine if they are equal.
Greater than Operator (>) Compares two expressions to determine if one is greater than the other.
Greater than or equal to Operator (>=) Compares two expressions to determine if one is greater than or equal to the other.
Identity Operator (===) Compares two expressions to determine if they are equal in value and of the same data type.
Increment Operator (++) Increments a variable by one.
Inequality Operator (!=) Compares two expressions to determine if they are unequal.
instanceof Operator Returns a Boolean value that indicates whether or not an object is an instance of a particular class.
Less than Operator (<) Compares two expressions to determine if one is less than the other.
Less than or equal to Operator (<=) Compares two expressions to determine if one is less than or equal to the other.
Logical AND Operator (&&) Performs a logical conjunction on two expressions.
Logical NOT Operator (!) Performs logical negation on an expression.
Logical OR Operator (||) Performs a logical disjunction on two expressions.
Modulus Operator (%) Divides two numbers and returns the remainder.
Multiplication Operator (*) Multiplies two numbers.
new Operator Creates a new object.
Nonidentity Operator (!==) Compares two expressions to determine that they are not equal in value or of the same data type.
Operator Precedence List containing information about the execution precedence of JScript operators.
Subtraction Operator (-) Performs subtraction of two expressions.
typeof Operator Returns a string that identifies the data type of an expression.
Unary Negation Operator (-) Indicates the negative value of a numeric expression.
Unsigned Right Shift Operator (>>>) Performs an unsigned right shift of the bits in an expression.
void Operator Prevents an expression from returning a value.
Language Element
 Description
$1...$9 Properties Returns the nine most-recently memorized portions found during pattern matching.
arguments Property Returns an array containing each argument passed to the currently executing function.
caller Property Returns a reference to the function that invoked the current function.
constructor Property Specifies the function that creates an object.
description Property Returns or sets the descriptive string associated with a specific error.
E Property Returns Euler's constant, the base of natural logarithms.
index Property Returns the character position where the first successful match begins in a searched string.
Infinity Property Returns an initial value of Number.POSITIVE_INFINITY.
input Property Returns the string against which a search was performed.
lastIndex Property Returns the character position where the last successful match begins in a searched string.
length Property (Array) Returns an integer value one higher than the highest element defined in an array.
length Property (Function) Returns the number of arguments defined for a function.
length Property (String) Returns the length of a String object.
LN2 Property Returns the natural logarithm of 2.
LN10 Property Returns the natural logarithm of 10.
LOG2E Property Returns the base-2 logarithm of e, Euler's constant.
LOG10E Property Returns the base-10 logarithm of e, Euler's constant.
MAX_VALUE Property Returns the largest number that can be represented in JScript.
MIN_VALUE Property Returns the number closest to zero that can be represented in JScript.
NaN Property (Global) Returns the special value NaN indicating that an expression is not a number.
NaN Property (Number) Returns the special value (NaN) indicating that an expression is not a number.
NEGATIVE_INFINITY Property Returns a value more negative than the largest negative number (-Number.MAX_VALUE) that can be represented in JScript.
number Property Returns or sets the numeric value associated with a specific error.
PI Property Returns the ratio of the circumference of a circle to its diameter, approximately 3.141592653589793.
POSITIVE_INFINITY Property Returns a value larger than the largest number (Number.MAX_VALUE) that can be represented in JScript.
prototype Property Returns a reference to the prototype for a class of objects.
source Property Returns a copy of the text of the regular expression pattern.
SQRT1_2 Property Returns the square root of 0.5, or one divided by the square root of 2.
SQRT2 Property Returns the square root of 2.
Language Element
 Description
break Statement Terminates the current loop, or if in conjunction with a label, terminates the associated statement.
catch Statement Contains statements to execute when an error occurs in code within the try block.
@cc_on Statement Activates conditional compilation support.
// (Single-line Comment Statement) Causes single-line comments to be ignored by the JScript parser.
/*..*/ (Multiline Comment Statement) Causes multiline comments to be ignored by the JScript parser.
continue Statement Stops the current iteration of a loop, and starts a new iteration.
do...while Statement Executes a statement block once, and then repeats execution of the loop until a condition expression evaluates to false.
for Statement Executes a block of statements for as long as a specified condition is true.
for...in Statement Executes one or more statements for each element of an object or array.
function Statement Declares a new function.
@if Statement Conditionally executes a group of statements, depending on the value of an expression.
if...else Statement Conditionally executes a group of statements, depending on the value of an expression.
Labeled Statement Provides an identifier for a statement.
return Statement Exits from the current function and returns a value from that function.
@set Statement Creates variables used with conditional compilation statements.
switch Statement Enables the execution of one or more statements when a specified expression's value matches a label.
this Statement Refers to the current object.
throw Statement Generates an error condition that can be handled by a try...catch statement.
try Statement Implements error handling for JScript.
var Statement Declares a variable.
while Statement Executes a statement until a specified condition is false.
with Statement Establishes the default object for a statement.
Language Element
 Description
Run-time Errors List of JScript run-time errors
Syntax Errors List of JScript syntax errors

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