教程吧

实例如下：

<?php /** * @name thumb 缩略图函数 * @param sting $img_name 图片路径 * @param int $max_width 略图最大宽度 * @param int $max_height 略图最大高度 * @param sting $suffix 略图后缀(如"img_x.jpg"代表小图,"img_m.jpg"代表中图,"img_l.jpg"代表大图) * @return void */ function thumb($img_name,$max_width,$max_height,$path,$new_name) { $img_infos = getimagesize($img_name); $img_height = $img_infos[0];//图片高 $img_width = $img_infos[1]; //图片宽 $img_extension = ''; //图片后缀名 switch($img_infos[2]) { case 1: $img_extension = 'jpg'; break; case 2: $img_extension = 'jpg'; break; case 3: $img_extension = 'jpg'; break; default: $img_extension = 'jpg'; break; } $new_img_size = array(); $new_img_size['width'] = $max_width; $new_img_size['height'] = $max_height; $img_func = ''; //函数名称 $img_handle = ''; //图片句柄 $thum_handle = ''; //略图图片句柄 switch($img_extension) { case 'jpg': $img_handle = imagecreatefromjpg($img_name); $img_func = 'imagejpg'; break; case 'jpg': $img_handle = imagecreatefromjpg($img_name); $img_func = 'imagejpg'; break; case 'jpg': $img_handle = imagecreatefromjpg($img_name); imagesavealpha($img_handle, true); $img_func = 'imagejpg'; break; case 'jpg': $img_handle = imagecreatefromjpg($img_name); $img_func = 'imagejpg'; break; default: $img_handle = imagecreatefromjpg($img_name); $img_func = 'imagejpg'; break; } $quality = 100;//图片质量 if($img_func == 'imagejpg') { $quality = 9; } $thum_handle = imagecreatetruecolor($new_img_size['height'],$new_img_size['width']); imagealphablending($thum_handle,false);//这里很重要,意思是不合并颜色,直接用$img图像颜色替换,包括透明色; imagesavealpha($thum_handle,true);//这里很重要,意思是不要丢了$thumb图像的透明色; if(function_exists('imagecopyresampled')) { imagecopyresampled($thum_handle,$img_handle, 0, 0, 0, 0,$new_img_size['height'],$new_img_size['width'],$img_height,$img_width); } else { imagecopyresized($thum_handle,$img_handle, 0, 0, 0, 0,$new_img_size['height'],$new_img_size['width'],$img_height,$img_width); } call_user_func_array($img_func,array($thum_handle,$path.'/'.$new_name,$quality)); imagedestroy($thum_handle);//清除句柄 imagedestroy($img_handle);//清除句柄 } $IconArray = array ( "IOS8" => array ( array("width" => 180, "height"=> 180, "path"=>"ios8", "name"=>"Icon-180.jpg"), array("width" => 120, "height"=> 120, "path"=>"ios8", "name"=>"Icon-120.jpg"), array("width" => 152, "height"=> 152, "path"=>"ios8", "name"=>"Icon-152.jpg"), array("width" => 76, "height"=> 76, "path"=>"ios8", "name"=>"Icon-76.jpg"), array("width" => 144, "height"=> 144, "path"=>"ios8", "name"=>"Icon-144.jpg"), array("width" => 72, "height"=> 72, "path"=>"ios8", "name"=>"Icon-72.jpg"), array("width" => 114, "height"=> 114, "path"=>"ios8", "name"=>"Icon-114.jpg"), array("width" => 57, "height"=> 57, "path"=>"ios8", "name"=>"Icon-57.jpg"), array("width" => 100, "height"=> 100, "path"=>"ios8", "name"=>"Icon-100.jpg"), array("width" => 50, "height"=> 50, "path"=>"ios8", "name"=>"Icon-50.jpg"), array("width" => 80, "height"=> 80, "path"=>"ios8", "name"=>"Icon-80.jpg"), array("width" => 40, "height"=> 40, "path"=>"ios8", "name"=>"Icon-40.jpg"), array("width" => 58, "height"=> 58, "path"=>"ios8", "name"=>"Icon-58.jpg"), array("width" => 29, "height"=> 29, "path"=>"ios8", "name"=>"Icon-29.jpg"), ), "IOS" => array ( array("width" => 180, "height"=> 180, "path"=>"ios", "name"=>"Icon-60@3x.jpg"), array("width" => 120, "height"=> 120, "path"=>"ios", "name"=>"Icon-60@2x.jpg"), array("width" => 152, "height"=> 152, "path"=>"ios", "name"=>"Icon-76@2x.jpg"), array("width" => 76, "height"=> 76, "path"=>"ios", "name"=>"Icon-76.jpg"), array("width" => 144, "height"=> 144, "path"=>"ios", "name"=>"Icon-72@2x.jpg"), array("width" => 72, "height"=> 72, "path"=>"ios", "name"=>"Icon-72.jpg"), array("width" => 114, "height"=> 114, "path"=>"ios", "name"=>"Icon-57@2x.jpg"), array("width" => 57, "height"=> 57, "path"=>"ios", "name"=>"Icon-57.jpg"), array("width" => 100, "height"=> 100, "path"=>"ios", "name"=>"Icon-50@2x.jpg"), array("width" => 50, "height"=> 50, "path"=>"ios", "name"=>"Icon-50.jpg"), array("width" => 80, "height"=> 80, "path"=>"ios", "name"=>"Icon-40@2x.jpg"), array("width" => 40, "height"=> 40, "path"=>"ios", "name"=>"Icon-40.jpg"), array("width" => 58, "height"=> 58, "path"=>"ios", "name"=>"Icon-29@2x.jpg"), array("width" => 29, "height"=> 29, "path"=>"ios", "name"=>"Icon-29.jpg"), ) , "ANDROID" => array ( array("width" => 144, "height" => 144, "path" => "android/drawable", "name"=>"icon.jpg"), array("width" => 144, "height" => 144, "path" => "android/drawable-xhdpi", "name"=>"icon.jpg"), array("width" => 72, "height" => 72, "path" => "android/drawable-hdpi", "name"=>"icon.jpg"), array("width" => 48, "height" => 48, "path" => "android/drawable-mdpi", "name"=>"icon.jpg"), array("width" => 32, "height" => 32, "path" => "android/drawable-ldpi", "name"=>"icon.jpg") ) ); foreach ($IconArray["IOS8"] as $key => $IconType) { thumb("icon.jpg",$IconType['width'],$IconType['height'],$IconType['path'],$IconType['name']); } foreach ($IconArray["IOS"] as $key => $IconType) { thumb("icon.jpg",$IconType['width'],$IconType['height'],$IconType['path'],$IconType['name']); } foreach ($IconArray["ANDROID"] as $key => $IconType) { thumb("icon.jpg",$IconType['width'],$IconType['height'],$IconType['path'],$IconType['name']); } ?>