jquery $.get cannot read

In recent years, with the continuous development of front-end technology, JavaScript has become a proficient tool for more and more developers. The jquery framework has also become one of the most popular JavaScript frameworks. However, in the process of using jquery, you will inevitably encounter some problems. One of them is that the $.get method in jquery cannot read data. Today, we will discuss the causes and solutions to this problem, so that everyone can be more comfortable when using the jquery framework.

The role of $.get

Before understanding the problem of $.get, we must first know the role of this method. The $.get method is a very commonly used asynchronous request method in the jquery framework. It can send an asynchronous GET request to the specified URL and process the returned data after the request is successful. Its basic syntax is as follows:

$.get(url,data,success(data,status,xhr),dataType);

Among them, url represents the address to be requested; data represents the data sent to the server; success is the callback function after the request is successful, where data represents the returned data and status represents the response status. , xhr represents the XMLHttpRequest object; dataType represents the returned data format.

The reason why $.get cannot read data

When we use the $.get method, if we find that the data cannot be read, there may be the following reasons.

1. The requested url is incorrect

$.get method obtains data by sending an http request. If the requested url is incorrect or incomplete, then it cannot Get the data. Therefore, we need to make sure the url is correct.

2. Network connection problem

Unstable or blocked network connection may also cause the $.get method to be unable to read data. At this point, we need to check whether the network connection is normal.

3. Cross-domain request

If the requested URL is not in the same domain as the current page, a cross-domain request will occur. For security reasons, the browser will reject cross-domain requests, so the data cannot be read.

4. The server returns an error

If the data format returned by the server is incorrect or an error occurs, it will also cause the $.get method to be unable to read the data. At this point, we need to check if there is a problem with the server-side code.

Solution

When there is a problem that the $.get method cannot read data, we can take the following solutions.

1. Make sure the url is correct

First we need to make sure the requested url is correct. You can check whether the requested URL is correct by opening the developer tools and viewing the network request in the console, and observe the response status and returned data.

2. Check whether the network connection is normal

We can check whether the network connection is normal by visiting other websites to determine whether there is a network connection problem.

3. Use jsonp to solve cross-domain problems

If there are cross-domain requests, we can use jsonp to solve them. jsonp is a cross-domain method that obtains returned data by adding a callback function to the request. Its basic syntax is as follows:

$.ajax({
    url: url,
    dataType: 'jsonp',
    jsonpCallback: 'callback',
    success: function(data){
        //处理返回的数据
    }
});

Among them, url represents the address to be requested; dataType represents the returned data format as jsonp; jsonpCallback represents the name of the callback function; success is the callback function after the request is successful. The returned data will automatically call the callback function for processing.

4. Check whether there are problems with the server-side code

If the data format returned by the server-side is incorrect or an error occurs, it will also cause the $.get method to be unable to read the data. At this point, we need to check whether there is a problem with the server-side code and ensure that the returned data is in the correct format.

Conclusion

$.The inability of the get method to read data is one of the common problems in the jquery framework. This is mainly due to incorrect urls, network connection problems, cross-domain requests and server-side returns. Caused by errors and other reasons. When encountering these problems, we can solve the problem by checking whether the URL is correct, checking whether the network connection is normal, using jsonp to solve cross-domain problems, and checking whether there are problems with the server-side code. As long as we can analyze the problem in time and find solutions when we encounter problems when using the jquery framework, we can make better use of the jquery framework and get twice the result with half the effort in front-end development.

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