How does js or jq judge that all images have been loaded?

how does js or jq determine that all images have been loaded?

Javascript
Mar.07,2021

use the onload event of document, or if you only care about pictures, hook up the load event of img. 

$('img').on('load', function() {
    // xxx
});
 /**
 *
 * @param arr ['']
 * @returns {Array}
 */
function loadImg(arr) {
    var newimages = [];
    var arr = (typeof arr != "object") ? [arr] : arr  //
    for (var i = 0; i < arr.length; iPP) {
        newimages[i] = new Promise(function (resolve, reject) {
            var image = new Image();
            image.addEventListener('load', function listener() {
                resolve(image);
                this.removeEventListener('load', listener);
            });
            image.src = arr[i];
            image.addEventListener('error', reject);
        })
    }
    return newimages
}
Promise.all(loadImg(listPics)).then(function () {
    console.log('')
});

the processing scheme of loading all pictures used by the project before, I hope it can help you

onload event of js image, load of jq

then you need to know the number of pictures in advance. Add a counter in the load callback function

. 
var i = 0;
$('img').load(function(){
    iPP;
    if(i==x){
        ...
    }
});

you need https://www.npmjs.com/package.

Previous: Node.js, is installed on windows 10 but cannot be used on cmd, but works on powershell. Why?

Next: A local file is uploaded to Ciyun and githup? using git

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e427f0-43678.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1e427f0-43678.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?