# Function Reference

# StringIsUpper

Checks if a string contains only uppercase characters.

StringIsUpper ( "string" )

## Parameters

string | The string to check

## Return Value

Success: | 1.
Failure: | 0 if string contains non-uppercase characters.

## Remarks

As in other StringIs...() the check is stop if a Chr(0) is encountered inside the string.
Internally the C function is used to speed up the processing.
Note that digits/punctuation/whitespace will cause StringIsUpper() to return 0.

## Related

StringIsAlNum, StringIsAlpha, StringIsASCII, StringIsDigit, StringIsLower, StringIsSpace, StringIsXDigit, StringLower, StringUpper

## Example

    #include <MsgBoxConstants.au3>

    Local $sString = "UPPERCASESTRING" ; Check whether this string contains only uppercase characters.
    If StringIsUpper($sString) Then
        MsgBox($MB_SYSTEMMODAL, "", "The variable is an uppercase string")
    Else
        MsgBox($MB_SYSTEMMODAL, "", "The variable is not an uppercase string")
    EndIf