When did Internet Explorer add for..in loop support to JavaScript?

Question

If I remember correctly, older versions of Internet Explorer did not support the for..in .

I don’t know which versions, but this is not the easiest thing for Google.

According to Microsoft, it is supported in Quirks mode and in standard mode from IE 6 onwards:

• http://msdn.microsoft.com/en-us/library/ie/55wb2d34(v=vs.94).aspx (the "Requirements" section below)

What version of Internet Explorer has added support for this?

Answer 1

As far as I remember, every browser that supports JS should have support for ... in , since until recently this was the only way to list the keys of an object.

Answer 2

Supported at least in IE6 +. The for-in loop is in Ecmascript 3, whose browsers have been supported for a very long time. You should feel comfortable using for-ins like any other JS construct.

Answer 3

According to the official Microsoft website , here's what they say:

for...of Statement (JavaScript) Not supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards, Internet Explorer 11 standards. Not supported on Windows 8.1.