js图片上传及显示

html部分：

<form action='' method='post' name='myform'>
<input type='file' id='iptfileupload' onchange='show()' value='' />
<img src='1.jpg' alt='' id='img' />
</form>

js部分：

<script type="text/javascript">
function getPath(obj,fileQuery,transImg) {

var imgSrc = '', imgArr = [], strSrc = '' ;

if(window.navigator.userAgent.indexOf("MSIE")>=1){ // IE浏览器判断
if(obj.select){
obj.select();
var path=document.selection.createRange().text;
alert(path) ;
obj.removeAttribute("src");
imgSrc = fileQuery.value ;
imgArr = imgSrc.split('.') ;
strSrc = imgArr[imgArr.length - 1].toLowerCase() ;
if(strSrc.localeCompare('jpg') === 0 || strSrc.localeCompare('jpeg') === 0 || strSrc.localeCompare('gif') === 0 || strSrc.localeCompare('png') === 0){
obj.setAttribute("src",transImg);
obj.style.filter=
"progid:DXImageTransform.Microsoft.AlphaImageLoader(src='"+path+"', sizingMethod='scale');"; // IE通过滤镜的方式实现图片显示
}else{
//try{
throw new Error('File type Error! please image file upload..');
//}catch(e){
// alert('name: ' + e.name + 'message: ' + e.message) ;
//}
}
}else{
// alert(fileQuery.value) ;
imgSrc = fileQuery.value ;
imgArr = imgSrc.split('.') ;
strSrc = imgArr[imgArr.length - 1].toLowerCase() ;
if(strSrc.localeCompare('jpg') === 0 || strSrc.localeCompare('jpeg') === 0 || strSrc.localeCompare('gif') === 0 || strSrc.localeCompare('png') === 0){
obj.src = fileQuery.value ;
}else{
//try{
throw new Error('File type Error! please image file upload..') ;
//}catch(e){
// alert('name: ' + e.name + 'message: ' + e.message) ;
//}
}

}

} else{
var file =fileQuery.files[0];
var reader = new FileReader();
reader.onload = function(e){

imgSrc = fileQuery.value ;
imgArr = imgSrc.split('.') ;
strSrc = imgArr[imgArr.length - 1].toLowerCase() ;
if(strSrc.localeCompare('jpg') === 0 || strSrc.localeCompare('jpeg') === 0 || strSrc.localeCompare('gif') === 0 || strSrc.localeCompare('png') === 0){
obj.setAttribute("src", e.target.result) ;
}else{
//try{
throw new Error('File type Error! please image file upload..') ;
//}catch(e){
// alert('name: ' + e.name + 'message: ' + e.message) ;
//}
}

// alert(e.target.result);
}
reader.readAsDataURL(file);
}
}

function show(){
//以下即为完整客户端路径
var file_img=document.getElementById("img"),
iptfileupload = document.getElementById('iptfileupload') ;
getPath(file_img,iptfileupload,file_img) ;
}

</script>

效果：