enable/disable checkbox in IE

i want to enable/disable checkbox开发者_StackOverflow using jQuery. I am using

$("#checkbox").attr("disabled", true);

This works fine in FF but not in IE.

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$("#checkbox").attr("disabled", "disabled");

is correct and better

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$("#checkbox").attr("disabled", "disabled");

or if you are using jquery 1.6+

$("#checkbox").prop("disabled", true);