这篇文章主要介绍了js动态创建上传表单通过iframe模拟Ajax无刷新的具体实现,需要的朋友可以参考下

 代码如下: <script>  window.onload=function(){  upfile('file.php');  }      /*  ** url 路径  **/  function upfile(url){  //创建iframe  var iframe = document.createElement("iframe");  document.body.appendChild(iframe);  iframe.id = 'iframeName';  iframe.name = 'iframeName';  iframe.style.display = 'none';  //创建form  var turnForm = document.createElement("form");  document.body.appendChild(turnForm);  turnForm.method = 'post';  turnForm.action = url;  turnForm.encoding = "multipart/form-data";  turnForm.name = 'formNamer';  turnForm.target = 'iframeName';  //创建隐藏表单  var newElement = document.createElement("input");  newElement.setAttribute("name","inputname");  newElement.setAttribute("type","file");  newElement.setAttribute("value",'');  turnForm.appendChild(newElement);  }    //form提交  function formSubmit() {  //var res = document.formNamer.inputname.value;  document.formNamer.submit();  }    //返回值  function callback(result){  //window.parent.document.getElementById('iframeName').style.display = 'block'; 通过iframe 查看后台数据  if(result['error'] == 0){  document.getElementById('test').src= result['img'][1]+'/'+result['img'][2];  }else if(result['error'] == 1){  alert(result['meg']);  }else if(result['error'] == 2){  alert(result['meg']);  }else if(result['error'] == 3){  alert(result['meg']);  }else if(result['error'] == 4){  alert(result['meg']);  }else{  alert(result['meg']);  }    }    </script>    <a href="javascript:formSubmit()">上传</a>  <img src="http://blog.163.com/zhwxl_zyx/blog/img/pasic.jpg" id="test" width="200" height="200">    file.php   代码如下: <?php  header("content-Type: text/html; charset=Utf-8");    if(@is_uploaded_file($_FILES['inputname']['tmp_name'])){    $f = $_FILES['inputname'];  $name = $f["name"];  $size = $f["size"];  $type = $f["type"];  $fileName = $f["tmp_name"];    switch ($type) {  case 'image/jpg':$okType = true;  break;    case 'image/jpeg':$okType = true;  break;    case 'image/png':$okType = true;  break;    case 'image/gif':$okType = true;  break;  }    if($okType){  $error = $f["error"];  echo '文件名称:'.$name.'<br>';  echo '文件类型:'.$type.'<br>';  echo '文件大小:'.round($size/1024).'K<br>';  echo '文件临时存放路径:'.$fileName.'<br>';    $fileDir = dirname(__FILE__).'/img/upfile'.time().$name;  $img = explode('/',$fileDir);    move_uploaded_file($fileName, $fileDir);    $data = array();  $data['img'] = $img;  $data['name'] = $name;  $data['type'] = $type;  $data['size'] = $size;  $data['filename'] = $fileName;  $data['fileDir'] = $fileDir;    if($error==0){  /*echo '上传成功!';  echo '预览:';  echo "<img src="http://blog.163.com/zhwxl_zyx/blog/.$img[1].'/'.$img[2]." width='200' height='200'><br>";  echo '文件名称'.$img[2];*/  $data['error'] = 0;  exit("<script>parent.callback(".json_encode($data).");</script>");    }elseif($error==1){  $data['error'] = 1;  $data['meg'] = '超过了文件大小，在php.ini文件中设置';  exit("<script>parent.callback(".json_encode($data).");</script>");  }elseif ($error==2){  $data['error'] = 2;  $data['meg'] = '超过了文件的大小MAX_FILE_SIZE选项指定的值';  exit("<script>parent.callback(".json_encode($data).");</script>");  }elseif ($error==3){  $data['error'] = 3;  $data['meg'] = '文件只有部分被上传';  exit("<script>parent.callback(".json_encode($data).");</script>");  }elseif ($error==4){  $data['error'] = 4;  $data['meg'] = '没有文件被上传';  exit("<script>parent.callback(".json_encode($data).");</script>");  }else{  $data['meg'] = '上传文件大小为0';  exit("<script>parent.callback(".json_encode($data).");</script>");  }    }  }else{  $data['error'] = 4;  $data['meg'] = '没有文件被上传';  exit("<script>parent.callback(".json_encode($data).");</script>");  }  ?>