// 記錄當(dāng)前時(shí)間戳
var start_time = new Date().getTime()
// 圖片地址 后面加時(shí)間戳是為了避免緩存
 var cutSrc = window.ctx + '/touchsys/terminal/showCapture?terminalId=' + terminalId + '×trap=' +
 Math.random();
// 創(chuàng)建對象
var img = new Image()
// 改變圖片的src
 img.src = cutSrc;
// 定時(shí)執(zhí)行獲取寬高
var check = function(){
 // 只要任何一方大于0
 // 表示已經(jīng)服務(wù)器已經(jīng)返回寬高
    if (img.width>0 || img.height>0) {
        var diff = new Date().getTime() - start_time;
        document.body.innerHTML += '
        from:check : width:'+img.width+',height:'+img.height+', time:'+diff+'ms';
        clearInterval(set);
    }
}
var set = setInterval(check,40)
// 加載完成獲取寬高
img.onload = function(){
    var diff = new Date().getTime() - start_time;
    document.body.innerHTML += 'from:onload : width:'+img.width+',height:'+img.height+', time:'+diff+'ms';
        //在里面在做一些我們想處理的邏輯
};