php使用GD库创建图片缩略图的方法，
php使用GD库创建图片缩略图的方法，
本文实例讲述了php使用GD库创建图片缩略图的方法。分享给大家供大家参考。具体分析如下：
上传页面的静态html代码：
<html> <head> <title>文件上传</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> </head> <h1 id="文件上传">文件上传</h1> <form enctype="multipart/form-data" action="Upload.php" method="post"> <input name="upfile" type="file"><BR> <input type="submit" value="Submit"> </form> <body> </body> </html>
相应的Upload.php文件代码：
<?php
$uploadfile = "upfiles/".$_FILES['upfile']['name'];
//上传后文件所在的文件名和路径
$smallfile = "upfiles/small_".$_FILES['upfile']['name'];
//上传后缩略图文件所在的文件名和路径
if($_FILES['upfile']['type'] != "image/pjpeg")
{
echo "文件类型错误"; //输出错误信息
}
else
{
move_uploaded_file($_FILES['upfile']['tmp_name'], $uploadfile);
//上传文件
$dstW = 200; //设定缩略图的宽度
$dstH = 200; //设定缩略图的高度
$src_image = ImageCreateFromJPEG($uploadfile);
//读取JPEG文件并创建图像对象
$srcW = ImageSX($src_image); //获得图像的宽
$srcH = ImageSY($src_image); //获得图像的高
$dst_image = ImageCreateTrueColor($dstW,$dstH);
//创建新的图像对象
ImageCopyResized($dst_image,$src_image,0,0,0,0,$dstW,$dstH,$srcW,$srcH);
//将图像重定义大小后写入新的图像对象
ImageJpeg($dst_image,$smallfile); //创建缩略图文件
echo "文件上传完成<BR>"; //输出上传成功的信息
echo "<img src="/static/imghw/default1.png" data-src="$smallfile" class="lazy" mce_ alt="php使用GD库创建图片缩略图的方法，" ></img>";
//在页面上显示缩略图
}
?>
希望本文所述对大家的php程序设计有所帮助。
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