Undefined in JavaScript.

I was stuck for 2 hours on this. I kept getting ’The value of the property 'GetData' is null or undefined, not a Function object’. Finally, I caught the error and resolved it in my js file and the error went away.


The lesson is that undefined means you haven’t defined it yet. Make sure js file is error free and that you didn’t forget to include the js file. If there is a "semi colon" error, you could face such type of errors.



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