JavaScript
/*
* @param m_this当前文件对象
* @param id展示图片id
* @param wid压缩后宽度
* @param quality压缩质量
* */
function cutImageBase64(m_this,id,wid,quality) {
var file = m_this.files[0];
var URL = window.URL || window.webkitURL;
var blob = URL.createObjectURL(file);
var base64;
var img = new Image();
img.src = blob;
img.onload = function() {
var that = this;
//生成比例
var w = that.width,
h = that.height,
scale = w / h;
w = wid || w;
h = w / scale;
//生成canvas
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('2d');
$(canvas).attr({
width: w,
height: h
});
ctx.drawImage(that, 0, 0, w, h);
// 生成base64
base64 = canvas.toDataURL('image/jpeg', quality || 0.8);
$(id).attr('src',base64);
};
}
//调用
$(id).on('change',function(){
var m_this = this;
cutImageBase64(m_this,'#com_ImgPr03',400,0.8);
})
