js实现图片压缩zip下载功能

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我是靠谱客的博主迅速小懒虫，这篇文章主要介绍js实现图片压缩zip下载功能，现在分享给大家，希望可以做个参考。

需要引入jszip.min.js 以及 FileSaver.js

js代码

复制代码

$(function(){
    $('#imageExportBtn').click(function() { //导出图片按钮绑定事件
        packageImages();
    });
})

function packageImages(){
	var imgs = ['']; //放图片路径

//传入图片路径，返回base64
function getBase64(img){
	function getBase64Image(img,width,height) {//width、height调用时传入具体像素值，控制大小 ,不传则默认图像大小
	  var canvas = document.createElement("canvas");
	  canvas.width = width ? width : img.width;
	  canvas.height = height ? height : img.height;
	
	  var ctx = canvas.getContext("2d");
	  ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
	  var dataURL = canvas.toDataURL();
	  return dataURL;
	}
	var image = new Image();
	image.crossOrigin = 'Anonymous';
	image.src = img;
	var deferred=$.Deferred();
	if(img){
	  image.onload =function (){
	    deferred.resolve(getBase64Image(image));//将base64传给done上传处理
	  }
	  return deferred.promise();//问题要让onload完成后再return sessionStorage['imgTest']
	}
}

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$(function(){
    $('#imageExportBtn').click(function() { //导出图片按钮绑定事件
        packageImages();
    });
})

function packageImages(){
	var imgs = ['']; //放图片路径

	var imgBase64 = [];
	var imageSuffix = [];//图片后缀
	var imageNames = [];
	var zip = new JSZip();
    zip.file("readme.txt", "传输图n");
    var img = zip.folder("images");
    
	for(var i=0;i<imgs.length;i++){
		var src = imgs[i];
		var name = src.substring(71);
		imageNames.push(name);
		var suffix = src.substring(src.lastIndexOf("."));
		imageSuffix.push(suffix);
		
		 getBase64(imgs[i])
            .then(function(base64){
            	imgBase64.push(base64.substring(22));
//                  console.log(base64);//处理成功打印在控制台
            },function(err){
                  console.log(err);//打印异常信息
            }); 
           
	}
	function tt(){
		setTimeout(function(){
			if(imgs.length == imgBase64.length){
				for(var i=0;i<imgs.length;i++){
					img.file(imageNames[i], imgBase64[i], {base64: true});
				}
				zip.generateAsync({type:"blob"}).then(function(content) {
			        // see FileSaver.js
			        saveAs(content, "images.zip");
			    });		    
			}else{
//				console.log('imgs.length:'+imgs.length+',imgBase64.length:'+imgBase64.length);
				console.log('进度：'+imgBase64.length+'/'+imgs.length);
				tt();
			}
		},100);
		
	}
	tt();
	
}

//传入图片路径，返回base64
function getBase64(img){
	function getBase64Image(img,width,height) {//width、height调用时传入具体像素值，控制大小 ,不传则默认图像大小
	  var canvas = document.createElement("canvas");
	  canvas.width = width ? width : img.width;
	  canvas.height = height ? height : img.height;
	
	  var ctx = canvas.getContext("2d");
	  ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
	  var dataURL = canvas.toDataURL();
	  return dataURL;
	}
	var image = new Image();
	image.crossOrigin = 'Anonymous';
	image.src = img;
	var deferred=$.Deferred();
	if(img){
	  image.onload =function (){
	    deferred.resolve(getBase64Image(image));//将base64传给done上传处理
	  }
	  return deferred.promise();//问题要让onload完成后再return sessionStorage['imgTest']
	}
}