How would you check if a variable is null/undefined?

969

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How to get the contents of an input box using javascript?

1079

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What is isnan in javascript?

1053

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What does the delete operator do?

944

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What does undefined value mean in javascript?

1114

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How can you detect the client operating system using javascript?

1258

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What is unobtrusive javascript? How to add behavior to an element using javascript?

978

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Write a way by which you can do something on the close of the window ?

1113

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How to get value from dropdown (select) control?

1065

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How to hide javascript code from old browsers that dont run it?

1044

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How to force a page to go to another page using javascript ?

910

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What is strict mode in javascript?

1060

---

discuss scoping in javascript?

955

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What is the concept of “functions as objects” and how does this affect variable scope?

930

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What is the result of below given line of code in java script? 5+4+'7'?

907

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