How to execute GET requests in advance and process results under specific conditions in programming?

Using a method of executing a get request in advance and processing results under specific conditions

In programming, we often need to process the result of the get request initiated in advance after a certain condition is met. For example, when the mouse moves to an element on the page, process the result after the request is completed and open the link in the return result. The following are methods and examples to implement this function.

Problem background

The user wants to execute a get request in advance, and process the result of the request when the mouse moves to an element on the page, and open a link in the return result. The current implementation is to wait for the request to complete by delaying 1500ms, and then process the link in the return result. However, the user wants to find a method that does not require delay, and can determine whether the get request has been completed when opening the request result link.

Request function example

First, let’s take a look at the user-provided request function example:

 var jhref;
function getwebsite(s) {
    let xhrresult = '';
    jhref = 'http://aaa.com';
    gm_xmlhttprequest({
        method: 'get',
        url: jhref,
        onload: function (result) {
            xhrresult = result.status;
            let domnew = new domparser().parsefromstring(result.responsetext, 'text/html');
            let linkelement = domnew.queryselectorall('.item>a')[0];
            if(linkelement != undefined) {
                jhref = linkelement.href;
            } else {
                xhrresult = 404;
            }
        },
        oneError: function (result) {
            console.log(result);
        },
    });
}

getwebsite(text);

Processing the request result

When the mouse moves to an element, the user wants to execute the link in the return result, and must ensure that the get request has been completed before executing:

 window.open(jhref);

Solution

According to the provided code, it is impossible to directly tell whether you are using jquery or other frameworks. However, we can propose a general solution: store the state of the ajax request in a fixed location, so that the state can be read directly when used without delay.

In jquery, state can be stored on the dom:

 // $(document).data('requeststatus', 'pending');

// $(document).data('requeststatus', 'completed');
$(document).data('resultlink', jhref);

// in mouse movement event if ($(document).data('requeststatus') === 'completed') {
    window.open($(document).data('resultlink'));
}

In vue or react, state can be stored in the component's state:

 // in Vue this.requestStatus = 'pending';

// this.requestStatus = 'completed' when the request is completed;
this.resultLink = jhref;

// in mouse movement event if (this.requestStatus === 'completed') {
    window.open(this.resultLink);
}

In this way, we can directly read the requested state when the mouse moves to the element without waiting for a fixed delay time, thus achieving a more flexible and reliable interactive experience.

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