這篇文章主要介紹了基于GD2圖形庫(kù)的PHP生成圖片縮略圖類代碼分享,本文直接給出實(shí)現(xiàn)代碼和使用方法,需要的朋友可以參考下

要使用PHP生成圖片縮略圖,要保證你的PHP服務(wù)器安裝了GD2圖形庫(kù) 使用一個(gè)類生成圖片的縮略圖

1.使用方法

$resizeimage = new resizeimage("圖片源文件地址", "200", "100", "0","縮略圖地址");

//就只用上面的一句話,就能生成縮略圖,其中,源文件和縮略圖地址可以相同,200,100分別代表寬和高

2. 縮略圖類代碼

//使用如下類就可以生成圖片縮略圖,

<?php

class resizeimage

{

//圖片類型

var $type;

//實(shí)際寬度

var $width;

//實(shí)際高度

var $height;

//改變后的寬度

var $resize_width;

//改變后的高度

var $resize_height;

//是否裁圖

var $cut;

//源圖象

var $srcimg;

//目標(biāo)圖象地址

var $dstimg;

//臨時(shí)創(chuàng)建的圖象

var $im;

function resizeimage($img, $wid, $hei,$c,$dstpath)

{

$this->srcimg = $img;

$this->resize_width = $wid;

$this->resize_height = $hei;

$this->cut = $c;

//圖片的類型

$this->type = strtolower(substr(strrchr($this->srcimg,"."),1));

//初始化圖象

$this->initi_img();

//目標(biāo)圖象地址

$this -> dst_img($dstpath);

//--

$this->width = imagesx($this->im);

$this->height = imagesy($this->im);

//生成圖象

$this->newimg();

ImageDestroy ($this->im);

}

function newimg()

{

//改變后的圖象的比例

$resize_ratio = ($this->resize_width)/($this->resize_height);

//實(shí)際圖象的比例

$ratio = ($this->width)/($this->height);

if(($this->cut)=="1")

//裁圖

{

if($ratio>=$resize_ratio)

//高度優(yōu)先

{

$newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);

imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width,$this->resize_height, (($this->height)*$resize_ratio), $this->height);

ImageJpeg ($newimg,$this->dstimg);

}

if($ratio<$resize_ratio)

//寬度優(yōu)先

{

$newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);

imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, $this->resize_height, $this->width, (($this->width)/$resize_ratio));

ImageJpeg ($newimg,$this->dstimg);

}

}

else

//不裁圖

{

if($ratio>=$resize_ratio)

{

$newimg = imagecreatetruecolor($this->resize_width,($this->resize_width)/$ratio);

imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, ($this->resize_width)/$ratio, $this->width, $this->height);

ImageJpeg ($newimg,$this->dstimg);

}

if($ratio<$resize_ratio)

{

$newimg = imagecreatetruecolor(($this->resize_height)*$ratio,$this->resize_height);

imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, ($this->resize_height)*$ratio, $this->resize_height, $this->width, $this->height);

ImageJpeg ($newimg,$this->dstimg);

}

}

}

//初始化圖象

function initi_img()

{

if($this->type=="jpg")

{

$this->im = imagecreatefromjpeg($this->srcimg);

}

if($this->type=="gif")

{

$this->im = imagecreatefromgif($this->srcimg);

}

if($this->type=="png")

{

$this->im = imagecreatefrompng($this->srcimg);

}

}

//圖象目標(biāo)地址

function dst_img($dstpath)

{

$full_length = strlen($this->srcimg);

$type_length = strlen($this->type);

$name_length = $full_length-$type_length;

$name = substr($this->srcimg,0,$name_length-1);

$this->dstimg = $dstpath;

//echo $this->dstimg;

}

}

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