some questions about the typeof operator of IE9
Question
I have been learning the Definitive Guide of JavaScript.i got a question about the typeof opertor. I run the script "alert(typeof window.alert)" in IE9 it proved to be return "function". but if i remove the "DOCTYPE" definition at the top of the html,the result turn to be "object".
I want to know why "DOCTYPE" definition exists or not make a different result. can anyone help me ? 3Q!
2 answers
solution1
3 ACCPTED 2012-04-01 07:16:47
IE<=8 used to have peculiar object bindings, and the typeof operator returned object where it should have returned function .
Removing the doctype puts IE into quirks mode . This makes sure that older websites can be viewed and older scripts don't throw errors.
solution2
1 2012-04-01 07:17:22
I found this to be a good explanation:
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