XWidgetSoft Forum

Using Javascript, I have a loop that modifies the Attributes of some objects, how is it possible to check if the object exists before applying changes ?

I have tried several methods to test if the object exist, including -
if (typeof objectname == "undefined")
if (null == objectname)
if ("undefined" == typeof(objectname)

But any reference to an object that does not exist result in a "runtime error object does not exist"
Can anyone assist ?

you can input all objects you want to change into array.

_________________
Life is a myriad game... Just play it!

That should not happen... As of my understanding on JScript.
Well here's another way.
You can enclose in a try-catch block too. But before that please run this test widget. File comment: Test
ObjTest.XWidgetPkg [6.27 KiB]
Downloaded 173 times

It includes all the procedures used in JS that to detect the validity of an object. Please go through the code-behind.

Run the test. If it is successful it will write success. If any error is thrown, it will show error. In this case I'll assume that your script engine and/or some other code has a problem, coz that's the only way to test it. Try running my code and say.

SUGGESTION: A good program (here widget) never manipulates on non existent, uninitialized or nulled objects. I wonder what's your requirement. Looking forward for your widget to complete...

_________________
Life is a myriad game... Just play it!

Thank you digigamer
I have already enclosed it in a try catch block to skip the error but as you suggested this is not a good solution.
Your test widget works OK returning "Obj Doesnot exist"

I have modified the script to only address objects that already exist.
Thanks again for you help,