php实现文件预览功能

5年以前 | 阅读数：416 次 | 编程语言：PHP

上一篇博客是上传功能，本篇是上传后图片预览和更改：

代码如下：

1.yulan.php


    <!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>无标题文档</title>
    <style type="text/css">
    #yl{ width:200px; height:300px; background-image:url(images/timg1.jpg); background-size:200px 300px;}
    #file{ width:200px; height:300px; float:left; opacity:0;}
    </style>
    </head>

    <body>

    <form id="sc" action="ylchuli.php" method="post" enctype="multipart/form-data" target="shangchuan">


      <input type="hidden" name="tp" value="" id="tp" />

      <div id="yl">
        <input type="file" name="file" id="file" onchange="document.getElementById('sc').submit()" />
      </div>



    </form>

    <iframe style="display:none" name="shangchuan" id="shangchuan">
    </iframe>


    </body>

    <script type="text/javascript">

    //回调函数,调用该方法传一个文件路径，改变背景图
    function showimg(url)
    {
      var div = document.getElementById("yl");
      div.style.backgroundImage = "url("+url+")";

      document.getElementById("tp").value = url;
    }

    </script>

    </html>

2.ylchuli.php


    <?php

    if($_FILES["file"]["error"])
    {
      echo $_FILES["file"]["error"];
    }
    else
    {
      if(($_FILES["file"]["type"]=="image/jpeg" || $_FILES["file"]["type"]=="image/png")&& $_FILES["file"]["size"]<1024000)
      {
        $fname = "./images/".date("YmdHis").$_FILES["file"]["name"];  

        $filename = iconv("UTF-8","gb2312",$fname);

        if(file_exists($filename))
        {
          echo "<script>alert('该文件已存在！');</script>";
        }
        else
        {
          move_uploaded_file($_FILES["file"]["tmp_name"],$filename);


          $delurl = iconv("UTF-8","gb2312",$_POST["tp"]);
          unlink($delurl); //删除文件

          echo "<script>parent.showimg('{$fname}');</script>";
        }

      }
    }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。