https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css">

{ $("#myupload").ajaxForm({ dataType:'json',beforeSend:function(){ $(".progress").show(); },uploadProgress:function(event,position,@R_8_10586@l,percentCompletE){ var percentVal = percentComplete + '%'; $(".progress-bar").width(percentComplete + '%'); $(".progress-bar").html(percentVal); $(".sr-only").html(percentComplete + '%'); },success:function(data){ $(".progress").hide();

     if(data.error == "empty_name"){
         alert("文件上传非法,上传失败!");
         exit();
     };
     if(data.error == "large"){
         alert("图片上传不能大于2M,上传失败!");
         exit();
     };

/alert(data.error);/
if(data.error == "format"){
alert("图片格式错误,上传失败");
//alert(data.typE);
exit();
};

     //alert("上传成功!");
     //files.html("<b>"+data.name+"("+data.size+"k)</b> <span class='delimg' rel='"+data.pic+"'>删除</span>");
     $(".files").html("文件名: "+data.name+"<span class='delimg' rel='"+data.pic+"'>  del  </span>大小："+data.sizE);
     var img = "http://www.sandleft.com/test/input/upload/files/"+data.pic;
     $(".showimg").html("<img src='"+img+"'>");
     alert("上传成功!");
 },error:function(){
     alert("图片上传失败");
 }

});
$(".progress").hide();
});

<div class="pk-system-messages"&gt;</div> <h1 class="uk-h2 uk-text-center" style="margin-top:-100px;"&gt;文件上传</h1> <div class="pk-system-messages"&gt;</div> <div class="container-main"&gt; <h1>Ajax Image Uploader</h1> <p>A simple tutorial to explain image uploading using jquery ajax and php</p> <form id='myupload' action='new_upload.php' method='post' enctype='multipart/form-data'> <label for="file"&gt;Filename:</label> <input type="file" name="mypic" id="file"&gt;<br> <input type="submit" name="upload" class="btn btn-success" value="upload"&gt; </form> <div class="progress"&gt; <div class="progress-bar progress-bar-success progress-bar-Striped" role="progressbar" aria-valuenow="45" aria-valuemin="0" aria-valuemax="100" style="width: 0%"&gt; <span class="sr-only"&gt;0% Complete</span> </div> </div> <div class="files"&gt;</div> <div class="showimg"&gt;</div> </div> </div>

php;"> php class upload{

protected $file_path = "files"; //当前files存储文件夹

protected $file_size = 1024000;

protected $file_size = 5120000; //5M 用户上传
//检测文件是否为空
public function check_file($get_filE)
{
if (empty($get_filE))
{
$type = "check_file";
$arr = array('error'=>'empty_name','type'=>$typE);
echo json_encode($arr);
exit();
}
return true;
}

//检测文件类型
public function check_type($get_typE)
{
if (( $get_type == ".docx" ) || ( $get_type == ".doc" )) {

$types = $get_type;

}else{
$type = "check_type";
$arr = array('error'=>'format','type'=>$typE);
echo json_encode($arr);
exit();

}
return true;
}

//检测文件大小
public function check_size($get_filE)
{
if ( $get_file != "" ) {
if ( $get_file > $this->file_size ) {
$arr = array('error'=>'large');
echo json_encode($arr);
exit();
}
}else{
return false;
exit();
}
return true;
}

//文件保存
public function save_file($file_type,$file_tmp_Name)
{
$rand = rand(1000,9999);
$pics = date("ymdHis") . $rand . $file_type;
$path = $this->file_path."/".$pics;
$result = move_uploaded_file($file_tmp_name,$path);
if($result){
return $pics;
}else{
return false;
exit();
}

return $pics;

}

}
php文件上传处理
<?php
include("upload.class.php");
$up_obj = new upload();

$get_filename = $_FILES['mypic']['name'];
$get_fileSize = $_FILES['mypic']['size'];
$get_TmpFiles = $_FILES['mypic']['tmp_name'];

$get_fileType = strstr($get_filename,'.');

$check_result = $up_obj->check_file($get_fileName);

if($check_result){

//检查文件类型
$result_type = $up_obj->check_type($get_fileTypE);

//检查文件大小
if($result_typE){

$result_size = $up_obj->check_size($get_fileSizE);

if($result_sizE){
  //文件上传保存  
  $pics = $up_obj->save_file($get_fileType,$get_TmpFiles);   
  $size = round($get_fileSize/1024,2);
      $arr = array(
        'name' => $get_filename,'pic' => $pics,'size'=> $size,'error' => 2
     );

   //检查文件上传状态
   if($pics){
     echo json_encode($arr);
     /*
     执行上传完成逻辑.....
     */
  }   
}

}

}