<?php
require?'string.func.php';
function?verifyImage($type?=?1,?$length?=?4,?$sess_name?=?"verify")?{
	//?創建畫布
	//?通過GD庫做驗證碼
	$width?=?80;
	$height?=?30;
	$image?=?imagecreatetruecolor?(?$width,?$height?);
	$white?=?imagecolorallocate?(?$image,?255,?255,?255?);
	$black?=?imagecolorallocate?(?$image,?0,?0,?0?);
	//?用填充矩形填充畫布
	imagefilledrectangle?(?$image,?1,?1,?$width?-?2,?$height?-?2,?$white?);
	$chars?=?buildRandomString?(?$type,?$length?);
	
	$_SESSION?[$sess_name]?=?$chars;
	$fontfiles?=?array?(
			"MSYH.TTC",
			"MSYHBD.TTC",
			"SIMKAI.TTF",
			"SIMLI.TTF",
			"STZHONGS.TTF"?
	);
	for($i?=?0;?$i?<?$length;?$i?++)?{
		$size?=?mt_rand?(?14,?18?);
		$angle?=?mt_rand?(?-?15,?15?);
		$x?=?5?+?$i?*?$size;
		$y?=?mt_rand?(?20,?26?);
		$fontfile?=?"../fonts/"?.?$fontfiles?[mt_rand?(?0,?count?(?$fontfiles?)?-?1?)];
		$color?=?imagecolorallocate?(?$image,?mt_rand?(?50,?90?),?mt_rand?(?80,?200?),?mt_rand?(?100,?150?)?);
		$text?=?substr?(?$chars,?$i,?1?);
		imagettftext?(?$image,?$size,?$angle,?$x,?$y,?$color,?$fontfile,?$text?);
	}
	
		for($i?=?0;?$i?<?50;?$i++)?{
			imagesetpixel?(?$image,?mt_rand?(?0,?$width?-?1?),?mt_rand?(?0,?$height?-?1?),?$black?);
		}
	
	header?(?"content-type:image/gif"?);
	imagegif?(?$image?);
	imagedestroy?(?$image?);
}
?>



--?以上代碼能正常顯示驗證碼，但在getverify.php調用verifyImage()的函數的時候就顯示不出來。


<?php
require_once?'../include.php';
verifyImage();
?>

請問是怎么回事呢？

還有就是verifyImage()函數如果完全按照老師的加直線，就會出現錯誤，顯示不出驗證碼。