This article mainly introduces the file preview function in PHP in detail. It has certain reference value. Interested friends can refer to it.
The previous blog is about the upload function, and this article is about it. Image preview and changes after uploading:
<!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" />
<p id="yl">
<input type="file" name="file" id="file" onchange="document.getElementById('sc').submit()" />
</p>
</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 p = document.getElementById("yl");
p.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>";
}
}
}
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