Differences between contentWindow and contentdocument and IFRAME access

A> contentWindow is compatible with various browsers and the window objects of subwindows can be obtained. B> contentdocument Firefox support,> ie support for IE8. Obtain the Document Object of the subwindow. Compatible with document objects: var getiframedoc = function () {var iobj = document. createelement ("iframe"); document. getelementsbytagname ("body") [0]. appendchild (iobj); Return iobj. contentdocument | iobj.contentw.doc ument;} basic usage: 1) document. getelementbyid ("myiframe "). after obtaining the IFRAME object from contentWindow, you can use contentWindow to obtain the window object containing the page, and then you can access the page elements normally; 2) $ ("# myiframe") [0]. contentWindow jquery selector gets IFRAME. First, convert the jquery object to a DOM object, or use the get () method to convert it. 3) $ ("# myiframe") [0]. contentWindow. $ ("# dd "). val () can be used to perform page operations after obtaining the IFRAME window object; 4) $ ("# myiframe") [0]. contentWindow. username = "zhangsan"; you can pass parameters to the IFRAME page in this way, in the IFRAME page window. username can be used to obtain the value. username is a custom global variable. 5) on the IFRAME page, you can use parent to obtain the window on the home page. Then, you can access the elements on the parent page; 7) parent. $ ("# frame_a" {0}.content}{doc ument. getelmentbyid ("# frame_ B"); For calls between IFRAME pages of the same level, you must first obtain the parent window, and then call the IFRAME of the same level to obtain the window for operation;