Returns an integer specifying the start position of the first occurrence of one string within another.

Public Shared Function InStr(_
   ByVal Start As Integer, _
   ByVal String1 As String, _
   ByVal String2 As String, _
   Optional ByVal Compare As Microsoft.VisualBasic.CompareMethod _
) As Integer

Parameters

Start

Required. Numeric expression that sets the starting position for each search. If omitted, search begins at the first character position. The start index is 1 based.

String1

Required. String expression being searched.

String2

Required. String expression sought.

Compare

Optional. Specifies the type of string comparison. If Compare is omitted, the Option Compare setting determines the type of comparison. Specify a valid LCID (LocaleID) to use locale-specific rules in the comparison.

Settings

The compare argument settings are:

Return Values

Exceptions/Errors

Example

This example uses the InStr function to return the position of the first occurrence of one string within another.

Dim SearchString, SearchChar As String
Dim MyPos As Integer

SearchString ="XXpXXpXXPXXP"   ' String to search in.
SearchChar = "P"   ' Search for "P".

' A textual comparison starting at position 4. Returns 6.
MyPos = InStr(4, SearchString, SearchChar, CompareMethod.Text)   

' A binary comparison starting at position 1. Returns 9.
MyPos = InStr(1, SearchString, SearchChar, CompareMethod.Binary)

' Comparison is binary by default (last argument is omitted).
MyPos = InStr(SearchString, SearchChar)   ' Returns 9.

MyPos = InStr(1, SearchString, "W")   ' Returns 0.

See Also

InStrRev Function | Option Compare Statement | StrComp Function | ArgumentException