


Detailed explanation of the steps to obtain data across domains using jQuery using ajax
This time I will bring you a detailed explanation of the steps for jQuery to use ajax to obtain cross-domain data. What are the precautions for jQuery to use ajax to obtain cross-domain data. The following is a practical case, let's take a look.
A simple example of jQuery using ajax to obtain data across domains
var webMethod = "http://localhost:54473/Service1.asmx/HelloWorld"; jQuery.support.cors = true; //之前没有加这句老是提示no transport,我没去深想。 $.ajax ({ type: "POST", contentType: "application/x-www-form-urlencoded", dataType: "html", url: "http://www.*****.com", //这里是网址 success:function(data){alert(data);}, timeout:30000, error: function (XMLHttpRequest, textStatus, errorThrown) { alert(errorThrown); } });
ParametersoptionsType: Object
Type: Boolean
Type: Function
Type: Boolean
Type: Function
Callback function (called after the request is successful or failed).
Parameters: XMLHttpRequest object and a string describing the request type. This is an Ajax event. contentTypeType: String
Type: Object
$.ajax({ url: "test.html", context: document.body, success: function(){ $(this).addClass("done"); }});data
Type: String
Type: Function
Type: String
•"xml": Returns an XML document that can be processed with jQuery.
•"html": Return plain text HTML information; the included script tag will be executed when inserted into the dom.
•"script": Return plain text JavaScript code. Results are not automatically cached. Unless the "cache" parameter is set. Note: When making remote requests (not under the same domain), all POST requests will be converted into GET requests. (Because the DOM script tag will be used to load)
•"json": Return JSON data.
•"jsonp": JSONP format. When calling a function using JSONP form, such as "myurl?callback=?" jQuery will automatically replace ? with the correct function name to execute the callback function.
•"text": Return plain text string
error
Type: Function
Default value: Automatic judgment (xml or html). This function is called when the request fails.
has the following three parameters: XMLHttpRequest object, error message, (optional) captured exception object.
If an error occurs, the error message (the second parameter) may be "timeout", "error", "notmodified" and "parsererror" in addition to null.
This is an Ajax event.
global
Type: Boolean
Whether to trigger the global AJAX event. Default value: true. Setting to false will not trigger global AJAX events such as ajaxStart or ajaxStop which can be used to control different Ajax events.
ifModified
Type: Boolean
Get new data only when the server data changes. Default value: false. Use HTTP packet Last-Modified header information to determine. As of jQuery 1.4, it also checks the server-specified 'etag' to make sure the data has not been modified.
jsonp
Type: String
Override the name of the callback function in a jsonp request. This value is used to replace the "callback" part of the URL parameter in a GET or POST request such as {jsonp:'onJsonPLoad'} which will cause "onJsonPLoad=?" to be passed to the server.
jsonpCallback
Type: String
Specify a callback function name for jsonp request. This value will be used instead of the random function name automatically generated by jQuery. This is mainly used to allow jQuery to generate unique function names so that it is easier to manage requests and provide callback functions and error handling. You can also specify this callback function name when you want the browser to cache GET requests.
password
Type: String
Password used to respond to HTTP access authentication requests
processData
Type: Boolean
Default value: true. By default, the data passed in through the data option, if it is an object (technically speaking, as long as it is not a string), will be processed and converted into a query string to match the default content type "application/x-www-form-urlencoded" ". Set to false if you want to send DOM tree information or other information that you don't want to convert.
scriptCharset
Type: String
Only when the dataType is "jsonp" or "script" when requested, and the type is "GET" will it be used to force the charset to be modified. Usually only used when the local and remote content encodings are different.
success
Type: Function
The callback function after the request is successful.
Parameters: Data returned by the server and processed according to the dataType parameter; a string describing the status.
This is an Ajax event.
traditional
Type: Boolean
Set to true if you want to serialize data in the traditional way. Please refer to the jQuery.param method under the Tools category.
timeout
Type: Number
Set the request timeout (milliseconds). This setting overrides the global setting.
type
Type: String
Default value: "GET"). Request method ("POST" or "GET"), default is "GET". Note: Other HTTP request methods, such as PUT and DELETE can also be used, but are only supported by some browsers.
url
Type: String
Default value: Current page address. The address to send the request to.
username
Type: String
Username used to respond to HTTP access authentication requests.
xhr
Type: Function
Needs to return an XMLHttpRequest object. The default is ActiveXObject under IE and XMLHttpRequest otherwise. Used to override or provide an enhanced XMLHttpRequest object. This parameter was not available before jQuery 1.3.
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
Recommended reading:
5 years of summary experience of using Ajax
Summary of three methods for Ajax to achieve cross-domain access
Detailed analysis of Ajax usage skills in JS
The above is the detailed content of Detailed explanation of the steps to obtain data across domains using jQuery using ajax. For more information, please follow other related articles on the PHP Chinese website!

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