Where to use "var' in javascript programs
Possible Duplicate:
Difference between using var and not using var in JavaScript
Hello,
I am a self learned developer. Always, i write javascripts without the var for variables. But some javascripts use var for variables.
Both worked well for me. I am bit confused by this.
Is Writing scripts with var a standard form or they used only within classes ?
var limits the scope of a variable to the function it is declared in, if you don't use var you create a global.
Globals tend to lead to code that is hard to maintain and suffers from race conditions.
Always use var unless you have a very good reason not to.
If you don't use var , the variable will be global, not limited in the scope you're in (a problem for say another variable in the global space with the same name, you just over-wrote it, probably unintentionally).
Short version: always use var to be safe.
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