/*@file {dom} 目标文件输入框*/
/*@tar {dom} 预览图片目标*/
/* previewImage(this,'#preview'); //预览图片的功能*/
function previewImage(file,tar) {
var MAXWIDTH = 120; // 最大图片宽度
var MAXHEIGHT = 120; // 最大图片高度
if (file.files && file.files[0]) {
var img = $(tar)[0];
img.onload = function() {
var rect = getZoomParam(MAXWIDTH, MAXHEIGHT, img.offsetWidth, img.offsetHeight);
img.width = rect.width;
img.height = rect.height;
}
var reader = new FileReader();
reader.onload = function(evt) {
img.src = evt.target.result;
}
reader.readAsDataURL(file.files[0]);
} else {
//兼容IE
file.select();
var src = document.selection.createRange().text;
var img = $(tar)[0];
img.filters.item('DXImageTransform.Microsoft.AlphaImageLoader').src = src;
}
}
function getZoomParam(maxWidth, maxHeight, width, height) {
var param = { top: 0, left: 0, width: width, height: height };
if (width > maxWidth || height > maxHeight) {
rateWidth = width / maxWidth;
rateHeight = height / maxHeight;
if (rateWidth > rateHeight) {
param.width = maxWidth;
param.height = Math.round(height / rateWidth);
} else {
param.width = Math.round(width / rateHeight);
param.height = maxHeight;
}
}
param.left = Math.round((maxWidth - param.width) / 2);
param.top = Math.round((maxHeight - param.height) / 2);
return param;
}