8.8

Stopping Execution
When using a script, you may come to a point where you'd like the task to fail (raise an
error)and trigger your On Error tab under certain conditions. This can be done by using the
scripting language's built-in error features, described here.
Note that the value or description of the error will not be available to your error process if one is
used. However, when available, a description of the error message will be logged in the Watch
log.
VBScript
In VBSCript, the Err.Raise method will halt the execution of the script and trigger the On Error
tab. When using On Error Resume Next, raising an error will not stop execution. See MSDN for
the Raise method properties and this page for a list of available errors to raise. In the case of
VBScript, the error number used will determine the message shown in the log.
Dim s
s = Watch.GetJobInfo(9)
If (s = "") Then
Err.Raise 449 ' Raises Error #449: "Argument is not optional"
Else
' Do somethign with Job Info 9!
Watch.Log "Job Info 9's value is: " + s, 4
End If
JavaScript
JavaScript uses the throw statement within try to create an exception which, if not caught
using catch() , will cause the script execution to stop and the On Error tab to be triggered. See
this page on W3Schools.
var s;
s = Watch.GetJobInfo(9);
if (s == "") {
throw "Value Cannot be empty";
} else {
// Do something with Job Info 9!
Watch.Log("Job Info 9's value is: " + s,4);
}
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