The example in this article describes the method of sequentially loading images in javascript. Share it with everyone for your reference. The details are as follows:
Javascript monitors whether an image has been loaded. If the loading is completed, it will load the next image. It is not loaded from the server all at once to reduce server pressure.
Usable places: For example, when making an application similar to Google Maps, small pictures can be loaded one by one
function Load_pic(arr){ this.loop_f=function(i,o_file,len,f,obj){ if(i<len-1){ i=i+1; f(i,o_file,len,obj); } }; this.creat_pic=function(i,o_file,len,obj){ var f=arguments.callee, doc=document, image = doc.createElement("img"); image.src =o_file[i]; i<len?doc.getElementsByTagName("body")[0].appendChild(image):''; if(navigator.userAgent.indexOf("MSIE")>0){ if($.browser.version==6.0 || $.browser.version==9.0){ //IE9和IE6一样 微软真是怪异 image.onreadystatechange = function () { if (image.readyState == "complete"){ obj.loop_f(i,o_file,len,f,obj); } }; }else{ ie7imagetime = window.setInterval(function(){ var rs = image.readyState; if(rs=="complete"){ window.clearInterval(ie7imagetime); obj.loop_f(i,o_file,len,f,obj); }else{ return; } },200); } }else{ image.onload = function () { if (image.complete == true){ obj.loop_f(i,o_file,len,f,obj); } }; } }; if(arr.constructor===Array){ var len=arr.length, i=0; i<len?this.creat_pic(i,arr,len,this):''; }; } //调用方法 new Load_pic([ 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/0_0.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/0_1.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/0_2.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/0_3.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/1_0.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/1_1.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/1_2.gif', 'http://gomap.dashilan.cn/jquery-mobile/map/cq/1/img_1/1_3.gif' ]); //注意要调用jquery 用于判断浏览器
I hope this article will be helpful to everyone’s JavaScript programming design.