Heim >Backend-Entwicklung >PHP-Tutorial >php上传图片生成缩略图(GD库),_PHP教程
首先来一段简单的php上传图片生成缩略图的详细代码,分享给大家供大家参考,具体内容如下
<?php function createThumbnail($imageDirectory, $imageName, $thumbDirectory, $thumbWidth, $quality){ $details = getimagesize("$imageDirectory/$imageName") or die('Please only upload images.'); $type = preg_replace('@^.+(?<=/)(.+)$@', '$1', $details['mime']); eval('$srcImg = imagecreatefrom'.$type.'("$imageDirectory/$imageName");'); $thumbHeight = $details[1] * ($thumbWidth / $details[0]); $thumbImg = imagecreatetruecolor($thumbWidth, $thumbHeight); imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $thumbWidth, $thumbHeight, $details[0], $details[1]); eval('image'.$type.'($thumbImg, "$thumbDirectory/$imageName"'. (($type=='jpeg')?', $quality':'').');'); imagedestroy($srcImg); imagedestroy($thumbImg); } foreach ($_FILES["pictures"]["error"] as $key => $error) { if ($error == UPLOAD_ERR_OK) { $tmp_name = $_FILES["pictures"]["tmp_name"][$key]; $name = $_FILES["pictures"]["name"][$key]; move_uploaded_file($tmp_name, "data/$name"); createThumbnail("/location/of/main/image", $name, "/location/to/store/thumb", 120, 80); //120 = thumb width :: 80 = thumb quality (1-100) } } ?>
接下来再为大家推荐一个实例php使用GD库上传图片以及创建缩略图,直接看代码:
GD库是PHP进行图象操作一个很强大的库。
先在php.ini里增加一行引用:extension=php_gd2.dll
重启apache,做一个测试页var_dump(gd_info());输出数据表明GD库引用成功。
图片上传页面 upload.html
<html> <head> <meta http-equiv='Content-Type' content='text/html; charset=utf-8'> <title>图片上传</title> </head> <body> <h1>文件上传(只允许上传jpg类型图片)</h1> <form enctype="multipart/form-data" action="upload_img.php" method="post"> <input name="upfile" type="file"><br><br> <input type="submit" value="提交"> </form> </body> </html>
处理页面upload_img.php
<?php //上传图片保存地址 $uploadfile = "upfiles/".$_FILES['upfile']['name']; //缩略图保存地址 $smallfile = "upfiles/small_".$_FILES['upfile']['name']; if($_FILES['upfile']['type'] != "image/jpeg") { echo '文件类型错误'; } else { move_uploaded_file($_FILES['upfile']['tmp_name'],$uploadfile); //上传文件 $dstW=200;//缩略图宽 $dstH=200;//缩略图高 $src_image=ImageCreateFromJPEG($uploadfile); $srcW=ImageSX($src_image); //获得图片宽 $srcH=ImageSY($src_image); //获得图片高 $dst_image=ImageCreateTrueColor($dstW,$dstH); ImageCopyResized($dst_image,$src_image,0,0,0,0,$dstW,$dstH,$srcW,$srcH); ImageJpeg($dst_image,$smallfile); echo '文件上传成功<br>'; echo "<img src='$smallfile' / alt="php上传图片生成缩略图(GD库),_PHP教程" >"; } ?>
希望对大家学习php程序设计有所帮助,谢谢大家的支持。