There is a relationship between these two windows. The parent window parent.htm opens the child window son.htm
The child window can point to the parent window through window.opener. In this way, the object of the parent window can be accessed.
Advantages: Convenient value acquisition .As long as window.opener points to the parent window, you can access all objects.
Not only can you access the value, but you can also access the method of the parent window. There is no limit to the value length.
Disadvantage: There must be a relationship between the two windows. Just use The window opened by window.open. Cannot cross domain.
Post.htm
Read.htm
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