文件上传20180420 16:50

实例

<form  action="" enctype="multipart/form-data" method="post">
    <input type="hidden" name="MAX_FILE_SIZE" value="542488">
    <fieldset>
        <legend align="center">文件上传</legend>
        <p>
            <strong>选择文件：</strong>
            <input type="file" name="upload">
        </p>
    </fieldset>
    <p align="center">
        <button type="submit" name="submit">上传</button>
    </p>
</form>
<script src="http://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"></script>
<script>
    $('button').on('click',function(){
        $.post( 'upload.php','wenjian='+$('input[name="upload"]').val(),function(data){

        },'json')
    })
</script>

实例

<?php

if($_SERVER['REQUEST_METHOD'] == 'POST'){
    //检测是否有文件被上传
    if(isset($_FILES['upload'])){
        //设置一个允许上传的类型
        $allow = ['image/jpg','image/jpeg','image/png'];
//        检测用户上传的文件类型是否正确
        if(in_array($_FILES['upload']['name'],$allow)){
            //将用户文件上传到指定的临时目录：move_uploaded_file()
            if(move_uploaded_file($_FILES['upload']['tmp_name'],"upload/{$_FILES['upload']['name']}")){
                exit(json_encode(['status'=>0,'msg'=>'上传成功']));
            }
        }
    }
    //对上传错误进行处理
if ($_FILES['upload']['error'] > 0 ) {
   echo '<p>错误原因是:<strong>';

   switch ($_FILES['upload']['error']) {
      case 1:
         echo '文件超过了php.ini配置中设置的大小';
         break;
      case 2:
         echo '文件超过了表单中常量设置的大小';
         break;
      case 3:
         echo '仅有部分文件被上传';
         break;
      case 4:
         echo '没有文件被上传';
         break;
      case 6:
         echo '没有可用的临时文件夹';
         break;
      case 7:
         echo '磁盘已满,写入失败';
         break;
      case 8:
         echo '上传意外中止';
         break;
      
      default:
         echo '系统未知错误';
         break;
   }

   echo '</strong></p>';
   //保险起见,最好把创建的临时文件删除,当然系统也会在结束会话时自动清空
   if (file_exists($_FILES['upload']['tmp_name']) && is_file($_FILES['upload']['tmp_name'])) {
      unlink($_FILES['upload']['tmp_name']);
   }
}

}

?>