function reSizeImg($imgSrc, $resize_width, $resize_height, $isCut=false) {	//图片的类型	$type = substr ( strrchr ( $imgSrc, "." ), 1 );	//初始化图象	if ($type == "jpg") {		$im = imagecreatefromjpeg ( $imgSrc );	}	if ($type == "gif") {		$im = imagecreatefromgif ( $imgSrc );	}	if ($type == "png") {		$im = imagecreatefrompng ( $imgSrc );	}	//目标图象地址	$full_length = strlen ( $imgSrc );	$type_length = strlen ( $type );	$name_length = $full_length - $type_length;	$name = substr ( $imgSrc, 0, $name_length - 1 );	$dstimg = $name . "_s." . $type;	$width = imagesx ( $im );	$height = imagesy ( $im );	//生成图象	//改变后的图象的比例	$resize_ratio = ($resize_width) / ($resize_height);	//实际图象的比例	$ratio = ($width) / ($height);	if (($isCut) == 1) //裁图		{		if ($ratio >= $resize_ratio) //高度优先		{			$newimg = imagecreatetruecolor ( $resize_width, $resize_height );			imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, $resize_height, (($height) * $resize_ratio), $height );			ImageJpeg ( $newimg, $dstimg );		}		if ($ratio < $resize_ratio) //宽度优先		{			$newimg = imagecreatetruecolor ( $resize_width, $resize_height );			imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, $resize_height, $width, (($width) / $resize_ratio) );			ImageJpeg ( $newimg, $dstimg );		}	} else //不裁图	{		if ($ratio >= $resize_ratio) {			$newimg = imagecreatetruecolor ( $resize_width, ($resize_width) / $ratio );			imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, ($resize_width) / $ratio, $width, $height );			ImageJpeg ( $newimg, $dstimg );		}		if ($ratio < $resize_ratio) {			$newimg = imagecreatetruecolor ( ($resize_height) * $ratio, $resize_height );			imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, ($resize_height) * $ratio, $resize_height, $width, $height );			ImageJpeg ( $newimg, $dstimg );		}	}	ImageDestroy ( $im );}