Asc
Returns the corresponding ASCII or Unicode integer representation of a character
Declare Function Asc ( ByRef str As Const String, ByVal position As Integer = 1 ) As Ulong
Declare Function Asc ( ByVal str As Const ZString Ptr, ByVal position As Integer = 1 ) As Ulong
Declare Function Asc ( ByVal str As Const WString Ptr, ByVal position As Integer = 1 ) As Ulong
result = Asc( str [, position ] )
str
The raw character value stored at position in str.
If str is a String or a ZString, the UByte value at that position is returned. This will be a 7-bit ASCII code, or even a 8-bit character value from some code-page, depending on the string data stored in str.
If str is a WString, the UShort (Windows) or Ulong (Linux) value at that position is returned. This will be a 16bit value on Windows (WStrings use UTF16 there), or a 32bit value on Linux (WStrings use UTF32 there).
The function returns zero (0) if the string is a zero length string, position is less than one (1), or position is greater than the number of characters in str.
Chr performs the opposite function for ASCII strings, while WChr is the opposite for Unicode strings, returning a string containing the character represented by the code passed as an argument.
will produce the output:
Unicode example (Note to documentation editors: don't put inside %%(qbasic) markers or the Russian text will disappear!)
will produce the output:
Syntax
Declare Function Asc ( ByRef str As Const String, ByVal position As Integer = 1 ) As Ulong
Declare Function Asc ( ByVal str As Const ZString Ptr, ByVal position As Integer = 1 ) As Ulong
Declare Function Asc ( ByVal str As Const WString Ptr, ByVal position As Integer = 1 ) As Ulong
Usage
result = Asc( str [, position ] )
Parameters
str
The source string.
positionThe position in the string of a character.
Return Value
The raw character value stored at position in str.
Description
If str is a String or a ZString, the UByte value at that position is returned. This will be a 7-bit ASCII code, or even a 8-bit character value from some code-page, depending on the string data stored in str.
If str is a WString, the UShort (Windows) or Ulong (Linux) value at that position is returned. This will be a 16bit value on Windows (WStrings use UTF16 there), or a 32bit value on Linux (WStrings use UTF32 there).
The function returns zero (0) if the string is a zero length string, position is less than one (1), or position is greater than the number of characters in str.
Chr performs the opposite function for ASCII strings, while WChr is the opposite for Unicode strings, returning a string containing the character represented by the code passed as an argument.
Example
Print "the ascii code of 'a' is:"; Asc("a")
Print "the ascii code of 'b' is:"; Asc("abc", 2)
Print "the ascii code of 'b' is:"; Asc("abc", 2)
will produce the output:
the ascii code of 'a' is: 97 the ascii code of 'b' is: 98
Unicode example (Note to documentation editors: don't put inside %%(qbasic) markers or the Russian text will disappear!)
| dim a as wstring * 11 a = "Привет, мир" print "the Unicode of the second char of " & a & " is: " & asc(a) |
| the Unicode of the second char of Привет, мир is: 1088 |
Platform Differences
- DOS does not support the wide-character string version of Asc.
Differences from QB
- The optional position argument is new to FreeBASIC.
- QB does not support the wide-character string version of Asc
See also