其实这个的主要部分并不是一个jquery，但是必须使用到
php程序部分，也只需要这个一个php程序就可以了
www.corange.cn亲测
<?php
header("Content-Type: text/html; charset=utf-8");
@header( "Cache-Control: no-cache, must-revalidate" );
@header( "Pragma: no-cache" );
@header( "Last-Modified: " . gmdate( "D, d M Y H:i:s" ) . "GMT" );
if($_GET['act']=='upload'){
if($_POST['upload']=='upload'){
$updir ='upload/';
$uploadfile = $uploaddir . basename($_FILES['file']['name']);
$_FILES['file']['name']=strtolower($_FILES['file']['name']);
$tmp_filename=explode(".",$_FILES['file']['name']);
if($tmp_filename[(count($tmp_filename)-1)]=='jpg' || $tmp_filename[(count($tmp_filename)-1)]=='jpeg'){
$up_filename=$updir.md5($_FILES['file']['name'].$_FILES['file']['size']).".".$tmp_filename[(count($tmp_filename)-1)] ;
if(move_uploaded_file($_FILES['file']['tmp_name'],$up_filename)){
list($width, $height, $type, $attr) = getimagesize($up_filename);
$f1="<img src='$up_filename' id='ImageDrag' width='150'>";
echo '<script language="javascript">parent.$("#ImageDragContainer").html("'.$f1.'");</script>';
echo "<script>parent.myform.bigpic.value=''</script>";//修改时候直接替换掉原数据
echo "<script>parent.myform.bigpic.value+='",$up_filename,",",$width,",",$height,"'</script>";
echo "<script>location.href='?act=upload'</script>";exit;
}else{
echo "<script>alert('图片上传失败!');location.href='?act=upload'</script>";exit;
}
echo "<script>alert('图片上传失败,请注意上传格式，只支持jpg格式图片!');location.href='?act=upload'</script>";exit;
?>
<body style="padding:0px;margin:0px;">
<div style="margin:0px;padding:0px;font-size:12px;">
<FORM ACTION="?act=upload" METHOD="POST" enctype="multipart/form-data">
<input type="file" name="file" id="file" />
<input type="submit" name="button" id="button" value="上传" />
<input name="upload" type="hidden" id="upload" value="upload" /><input type="hidden" name="MAX_FILE_SIZE" value="3000000" />
</FORM>
</div>
</body>
exit;
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>上传照片,上传后可以预览-www.corange.cn 网站开发代码</title>
<script src="js/jquery.pack.js"></script>
</head>
<body>
<form action="upload_ok.php" name="myform">
<table width="700" border="0" cellpadding="3" cellspacing="1">
<tr>
<td width="250" valign="top" bgcolor="#FFFFFF">
<div id="ImageDragContainer">
</td>
<td valign="top" bgcolor="#FFFFFF">
<br><br>
<iframe frameborder=0 style="width:350px;height:50px;padding:0px;border:0px;background:#fff" src="?act=upload"></iframe><textarea cols="60" name="bigpic" rows="1" id="IconContainer"></textarea>
</tr>
</table>
<input name="" type="submit" />
</form>
</html>
Jquery请自行下载后测试
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