Javascript Runtime error in ASPX page

I got strange error when i run the .apsx page

Error is below:

"Microsoft JScript runtime error: Unable to 开发者_开发技巧get value of the property 'addEventListener': object is null or undefined"

I could not understand, why this error occur. How can i fix it plz help !

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If you are using IE, than perhaps it's because for IE<9, you need to use attachEvent. https://developer.mozilla.org/en/DOM/element.addEventListener