本地图片上传即时预览
// 图片预览功能
var preivew = function(file, container){
// 允许上传的图片格式
var allowExt = ['jpg', 'gif', 'bmp', 'png', 'jpeg'];
var Picture = function(file, container){
var height = 0, widht = 0, ext = '', size = 0, name = '', path = ''; var self = this;
var tempPath = '';
if(file){
name = file.value;
if (window.navigator.userAgent.indexOf("MSIE")>=1){
file.select();
tempPath = document.selection.createRange().text;
if(tempPath!=""){
path = tempPath;
}
}else if(file.files){
try{
path = file.files.item(0).getAsDataURL();
}catch(e){
? ?if(window.URL){
path = URL.createObjectURL(file.files[0]);
?? }
? ? ?}
? ? ??}else{
? ? ?path = file.value;
? ? ??}
? ? ? }else{
? throw "bad file";
}
ext = name.substr(name.lastIndexOf("."), name.length);
if(container.tagName.toLowerCase() != 'img'){
throw "container is not a valid img label";
container.visibility = 'hidden';
}
height = container.height;
widht = container.widht;
size = container.fileSize;
this.get = function(name){
return self[name];
}
this.isValid = function(){
if(allowExt.indexOf(self.ext) !== -1){
throw 'the ext is not allowed to upload';
return false;
??}
return true;
}
if(!this.isValid()){
alert('the ext is not allowed to upload');
return false;
??}
container.src = path;
container.alt = name;
};
try{
var pic = new Picture(file, container);
}catch(e){
alert(e);
}
};
