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Checks whether last plugin function returned error.

Component Version macOS Windows Linux Server iOS SDK
Plugin 3.4 ✅ Yes ✅ Yes ✅ Yes ✅ Yes ✅ Yes
MBS( "IsError" )




Returns 1 or 0.


Checks whether last plugin function returned error.
Returns 1 if last function returned an error.
Or returns 0 if no error happened.
This makes it easier to detect if the result text is an error message vs. a real result.

See also ClearErrors and HadErrors functions.


Cause an error and handle it:

Set Variable [ $r; Value:MBS( "ZipFile.Open"; "" ) ]
If [ MBS("IsError") ]
    Show Custom Dialog [ Title: "Error"; Message: $r; Buttons: "OK”, "Abbrechen” ]
    Exit Script [ ]
End If

See also

Release notes

  • Version 12.4
    • Fixed a problem where ErrorLog would show IsError function.

Blog Entries

This function is free to use.

Created 18th August 2014, last changed 28th April 2022

IsClient - IsIOS