头像上传预览

<!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>
</head>

<body>
<form id="sc" action="shangchuan.php" target="hidden_frame" method="post" enctype="multipart/form-data">
    <div id="yl" style="margin-left:0px; 144px; height:170px; background-size:144px 170px; background-image:url(../chexiangqing/images/22.jpg)">
        <input type="file" name="file" style="144px; height:170px; float:left; opacity:0;" width="146" onchange="document.getElementById('sc').submit()"/>
       
    </div>
    <input type="button" value="保存"/>
</form>
<iframe style="display:none;" name="hidden_frame" id="hidden_frame">
</iframe>

</body>
<script type="text/javascript">
//回调函数
function showimg(aa)
{
    var l = document.getElementById("yl");
    l.style.backgroundImage = "url("+aa+")";
}
</script>
</html>

处理页面

<?php
   //上传文件限制
   if ((($_FILES["file"]["type"] == "image/gif")|| ($_FILES["file"]["type"] == "image/jpeg")|| ($_FILES["file"]["type"] == "image/png"))&& ($_FILES["file"]["size"] < 10000000))
  {
      //文件上传是否出错
      if ($_FILES["file"]["error"] > 0)
    {
        echo "上传出错: " . $_FILES["file"]["error"] . "<br />";
    }
      else
    {
        
    
    //判断文件是否已存在
    $filename = "images/".$_FILES["file"]["name"];
    $filename = iconv("UTF-8","gb2312",$filename);
     
    if (file_exists($filename))
      {
          echo "<script language='javascript'>alert('文件已经存在!')</script>";
           
      }
    else
      {
          //移动图片至保存路径,解决中文乱码问题
            move_uploaded_file($_FILES["file"]["tmp_name"],$filename);

          echo "<script language='javascript'>parent.showimg('".$filename."')</script>";
      }
    }
  }
  else
  {
      echo "上传失败";
  }

?>
原文地址:https://www.cnblogs.com/xiaofox0018/p/6124788.html