JavaScript Ajax-2 Ajax (use Ajax to send GET requests, use AJAX to send post requests)

Tag: Browser server string User false

One, using Ajax to send a GET request

Steps to send an asynchronous request

-Get Ajax object: Get XMLHttpRequest Object instance

-Create Request: Call the Open method of the XMLHttpRequest object

-Set the callback function: Set the response function for the onreadystatechange event of the Ajax object

-Send request: Call the Send method of the Ajax object

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-Create Request

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Note

-true: Indicates the sending of an asynchronous request (the user can still do other things to the current page when the Ajax object sends the request)

-False: Indicates the sending of a synchronization request (when the Ajax object sends a request, the browser locks the current page and the user cannot do anything else on the current page)

-Set callback function

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-Send Request

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Writing server-side code

-The server typically returns part of the data, such as a simple text

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Second, use Ajax to send a POST request

Send string

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-POST Request:

-Need to manually set the request message header to application/x-www-form-urlencoded

-A commit parameter is passed within the Send method, and no nullable

Summary: This chapter focuses on Ajax (using AJAX to send a GET request, using AJAX to send a POST request)

This article from the "Flying Ants" blog, declined to reprint!

JavaScript Ajax-2 Ajax (use Ajax to send GET requests, use AJAX to send post requests)