Java 中 request.setAttribute 有什么用？

Question

I can understand that it's like assigning a value to a key. For ex: request.setAttribute("listedit", people);

where people is a string. How it will assign people to "listedit" and where/how the key should be used?

Answer 1

It's just an attribute Map . Most commonly your view (JSP or other) will access the values by key, so you can write something like Hello ${name} in your view, and the value bound to the key "name" will then be displayed.

Answer 2

request.setAttribute only make the key available in the following jsp page.

For example, the flow like page1->page2, if we use request.setAttribute in page1, then only page2 can get the key value set in page2.

request.setAttribute(): 1.May help you in getting rid of the hidden fields. 2.Use it most of times when you just need the attribute just for the consecutive page.