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.

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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-64f5-1b39bcb-2c19b.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b39bcb-2c19b.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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