文件上传实例: 无刷新 & 重命名 & 回调

重命名 : 为防止文件名重复, 使用的规则是 年月日时分秒 + 随机数序
Ajax & callback : use jquery.form.js

html+js:

<html>
<body>

<!--表单-->
<form action="upload_file.php" method="post" enctype="multipart/form-data" id="xhdform">
	<input type="file" name="file" id="file" />
	<input type="hidden" name="xxx" />
	<input type="submit" name="submit" value="Submit" />
</form> 

<div id="ooo"> <!--where to callback--> </div>

<script src="/jquery.min.js"></script>   
<script src="/jquery.form.js"></script> 
<script type="text/javascript">
	//JQ
	$(document).ready(function() {
		$('#xhdform').submit(function() {
			var options = {
				target: '#ooo', //where to callback
				url: 'upload_file.php', //form的action地址
				type: 'post',
				success: function() {
					$('#xxx').val($('#ooo').text());  //what to callback
				}
			};
			$(this).ajaxSubmit(options);
			return false;
		});
	});
</script>
</body>
</html>

upload_file.php:

<?php 
$folder = 'upload/';
if (! file_exists ( $folder )) {mkdir ( $folder );}//新增: create folder "upload"
if ((($_FILES["file"]["type"] == "image/gif") || ($_FILES["file"]["type"] == "image/jpg") || ($_FILES["file"]["type"] == "image/png")) // 允许上传的文件类型
&& ($_FILES["file"]["size"] < 20000)) // max size
if( preg_match( "#^image/((?:gif)|(?:jpg)|(?:jpeg)|(?:png))$#is", $_FILES["file"]["type"], $match ) && ($_FILES["file"]["size"] < 2097152) )
// 20000差不多是20kb太小了, 刚才修改了一下, 改成2M; 另外此行preg_match和上面["file"]["type"]==的效果一样
  {
  if ($_FILES["file"]["error"] > 0)
    {
    echo "Return Code: " . $_FILES["file"]["error"] . "<br />";
    }
  else
    {
    echo "Upload: " . $_FILES["file"]["name"] . "<br />";
    echo "Type: " . $_FILES["file"]["type"] . "<br />";
    echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />";
    echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />";

    if (file_exists("upload/" . $_FILES["file"]["name"])) // if file already exists
      {
      echo $_FILES["file"]["name"] . " already exists. ";
      }

    else
      {
		// rename rule begin ~~~~ xiaohudie
		for ( $i=0; $i<10; $i++ )
		$rand = substr($rand2,mt_rand(0,strlen($rand2)-1),1);
		$rand2 = '1234567890abcdefghijklmnopgrstuvwxyz';
		$id = date("YmdHis").'_'.$rand;  //输出格式例如: 20130503112737_npcajvurig 
		move_uploaded_file(   $_FILES["file"]["tmp_name"],  "upload/" . $id  .".jpg"  ); //在upload文件夹保存图片并重命名, 添加.jpg后缀
		echo "Stored in: " . "upload/" . $id  .".jpg";
		
      }
    }
  }
else
  {
  echo "Invalid file";
  }  
?>

代码写多了感觉自己中文跟不上节奏了, 专注装逼十九年其实我想用全英文写注释的

file_upload is coded by http://xiaohudie.net. Any posts here is one hundred percent original, so please keep my link so as not to hurt this pretty girl. -小蝴蝶