InStr
Locates the first occurrence of a substring or character within a string
Declare Function InStr ( ByRef str As Const String, [ Any ] ByRef substring As Const String ) As Integer
Declare Function InStr ( ByRef str As Const WString, [ Any ] ByRef substring As Const WString ) As Integer
Declare Function InStr ( ByVal start As Integer, ByRef str As Const String, [ Any ] ByRef substring As Const String ) As Integer
Declare Function InStr ( ByVal start As Integer, ByRef str As Const WString, [ Any ] ByRef substring As Const WString ) As Integer
first = InStr( [ start, ] str, [ Any ] substring )
str
The position of the first occurrence of substring in str.
Locates the position of the first occurrence of a substring or character within a string. In the first form of InStr (without start parameter), the search begins at the first character.
Zero (0) is returned if: either substring is not found, either str or substring are empty strings, or start < 1.
If the Any keyword is specified, InStr returns the first occurrence of any character in substring.
Syntax
Declare Function InStr ( ByRef str As Const String, [ Any ] ByRef substring As Const String ) As Integer
Declare Function InStr ( ByRef str As Const WString, [ Any ] ByRef substring As Const WString ) As Integer
Declare Function InStr ( ByVal start As Integer, ByRef str As Const String, [ Any ] ByRef substring As Const String ) As Integer
Declare Function InStr ( ByVal start As Integer, ByRef str As Const WString, [ Any ] ByRef substring As Const WString ) As Integer
Usage
first = InStr( [ start, ] str, [ Any ] substring )
Parameters
str
The string to be searched.
substringThe substring to find.
startThe position in str at which the search will begin. The first character starts at position 1.
Return Value
The position of the first occurrence of substring in str.
Description
Locates the position of the first occurrence of a substring or character within a string. In the first form of InStr (without start parameter), the search begins at the first character.
Zero (0) is returned if: either substring is not found, either str or substring are empty strings, or start < 1.
If the Any keyword is specified, InStr returns the first occurrence of any character in substring.
Example
' It will return 4
Print InStr("abcdefg", "de")
' It will return 0
Print InStr("abcdefg", "h")
' It will search for any of the characters "f", "b", "c", and return 2 as "b" is encountered first
Print InStr("abcdefg", Any "fbc")
Print InStr("abcdefg", "de")
' It will return 0
Print InStr("abcdefg", "h")
' It will search for any of the characters "f", "b", "c", and return 2 as "b" is encountered first
Print InStr("abcdefg", Any "fbc")
Dim test As String
Dim idx As Integer
test = "abababab"
idx = InStr(test, "b")
Do While idx > 0 'if not found loop will be skipped
Print """b"" at " & idx
idx = InStr(idx + 1, Test, "b")
Loop
Dim idx As Integer
test = "abababab"
idx = InStr(test, "b")
Do While idx > 0 'if not found loop will be skipped
Print """b"" at " & idx
idx = InStr(idx + 1, Test, "b")
Loop
| 'A Unicode example: dim text as wstring*20 text = "Привет, мир!" print instr(text,"ет") ' displays 5 |
Platform Differences
- The wide-character string version of InStr is not supported for DOS target.
Differences from QB
- QB returns start if search is a zero length string.
- QB does not support Unicode.
See also