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StrComp Function (Visual Basic) 

  • Article

Returns -1, 0, or 1, based on the result of a string comparison.

Public Shared Function StrComp( _
   ByVal String1 As String, _
   ByVal String2 As String, _
   <Microsoft.VisualBasic.OptionCompareAttribute> _
   Optional ByVal Compare As Microsoft.VisualBasic.CompareMethod _
) As Integer

Parameters

  • String1
    Required. Any valid String expression.
  • String2
    Required. Any valid String expression.
  • Compare
    Optional. Specifies the type of string comparison. If Compare is omitted, the Option Compare setting determines the type of comparison.

Settings

The Compare argument settings are:

Constant Description

Binary

Performs a binary comparison, based on a sort order derived from the internal binary representations of the characters.

Text

Performs a text comparison, based on a case-insensitive text sort order determined by your system's LocaleID value.

Return Value

The StrComp function has the following return values.

If StrComp returns

String1 sorts ahead of String2

-1

String1 is equal to String2

0

String1 sorts after String2

1

Exceptions

Exception type Error number Condition

ArgumentException

5

Compare value is not valid .

See the "Error number" column if you are upgrading Visual Basic 6.0 applications that use unstructured error handling. (You can compare the error number against the Number Property (Err Object).) However, when possible, you should consider replacing such error control with Structured Exception Handling Overview for Visual Basic.

Remarks

The strings are compared by alphanumeric sort values beginning with the first character. For further information on binary comparisons, textual comparisons, and sort order, see Option Compare Statement.

Example

This example uses the StrComp function to return the results of a string comparison. If the third argument is omitted, the comparison type defined in the Option Compare statement or project defaults is performed.

' Defines variables.
Dim TestStr1 As String = "ABCD"
Dim TestStr2 As String = "abcd"
Dim TestComp As Integer
' The two strings sort equally. Returns 0.
TestComp = StrComp(TestStr1, TestStr2, CompareMethod.Text)
' TestStr1 sorts after TestStr2. Returns -1.
TestComp = StrComp(TestStr1, TestStr2, CompareMethod.Binary)
' TestStr2 sorts before TestStr1. Returns 1.
TestComp = StrComp(TestStr2, TestStr1)

Requirements

Namespace: Microsoft.VisualBasic

Module: Strings

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

See Also

Reference

String Manipulation Summary
InStr Function (Visual Basic)
ArgumentException

Other Resources

Strings in Visual Basic
Introduction to Strings in Visual Basic