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PHP implements avatar upload preview function_php example

墨辰丷

May 23, 2018 pm 02:19 PM

phpFunctionPreview

This article mainly introduces the relevant information of PHP to implement the avatar upload preview function in detail. It has certain reference value. Interested friends can refer to

Main page 1.php

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>上传头像</title>
<style type="text/css">
  *{
    font-family:"微软雅黑";}
  #zong{
    /*border:1px solid black;*/
    position:relative;
    width:52%;
    height:500x;
    left:24%}
  .nr{
    float:left;
    margin-right:30px;}
  #yl{width:240px; height:240px; background-size:240px 240px;}
  #file{width:240px; height:240px; float:left; opacity:0;}
</style>
</head>

<body>

<p id="zong">
<form id="sc" action="2.php" method="post" enctype="multipart/form-data" target="shangchuan">
  
  <input type="hidden" name="tp" value="" id="tp" />
  
  <p id="yl" style="background-image:url(./image/1.jpg)" class="nr">//头像显示的位置
    <input type="file" name="file" id="file" onchange="document.getElementById(&#39;sc&#39;).submit()" />
  </p>
  <p class="nr">
  </p> 
</form>

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

</p>
</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 p = document.getElementById("yl");
  p.style.backgroundImage = "url("+url+")";
  
  document.getElementById("tp").value = url;
}

</script>

</html>

Processing page 2.php

<?php
session_start();
$uid = $_SESSION["uid"];
if($_FILES["file"]["error"])
{
  echo $_FILES["file"]["error"];
}
else
{
  if(($_FILES["file"]["type"]=="image/jpeg" || $_FILES["file"]["type"]=="image/png")&& $_FILES["file"]["size"]<1024000)
  {
    $fname = "./a/image/".date("YmdHis").$_FILES["file"]["name"];  //头像存储的路径
    
    $filename = iconv("UTF-8","gb2312",$fname);
    
    if(file_exists($filename))
    {
      echo "<script>alert(&#39;该文件已存在！&#39;);</script>";
    }
    else
    {
      move_uploaded_file($_FILES["file"]["tmp_name"],$filename);
      
      unlink($_POST["tp"]);
      echo "<script>parent.showimg(&#39;{$fname}&#39;);</script>";
    }
    
  }
}

Open the display:

Click the picture location to pop up the selection box:

After selecting the picture:

The above is the entire content of this article, I hope it will be helpful to everyone's study.

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