function previewImg(self,imgId ) {
var url=createObjectUrl(self.files[0]);
document.getElementById(imgId).src=url;
}
function createObjectUrl(Blob) {
if(window.URL){
return window.URL.createObjectURL(Blob);
}else if(window.webkitURL){
return window.webkitURL.createObjectURL(Blob)
}
}