把GB码转换到UTF8,php中TTF支持UTF8编码的非ASCII字符输出.在分析这段代码之后,发现可以实现中文与ASCII混合输出图象,这样在我们操作图象函数时可以更方便.

代码如下:

<?

function gb2utf8($gb)

{

if(!trim($gb))

return $gb;

$filename="gb2312.txt";

$tmp=file($filename);

$codetable=array();

while(list($key,$value)=each($tmp))

$codetable[hexdec(substr($value,0,6))]=substr($value,7,6);

$utf8="";

while($gb)

{

if (ord(substr($gb,0,1))>127)

{

$this=substr($gb,0,2);

$gb=substr($gb,2,strlen($gb)-2);

$utf8.=u2utf8(hexdec($codetable[hexdec(bin2hex($this))-0x8080]));

}

else

{

$this=substr($gb,0,1);

$gb=substr($gb,1,strlen($gb)-1);

$utf8.=u2utf8($this);

}

}

/*$ret="";

for($i=0;$i<strlen($utf8);$i+=3)

$ret.=chr(substr($utf8,$i,3));

return $ret;*/

return $utf8;

}

function u2utf8($c)

{

/*for($i=0;$i<count($c);$i++)*/

$str="";

if ($c < 0x80) {

$str.=$c;

}

else if ($c < 0x800) {

$str.=chr(0xC0 | $c>>6);

$str.=chr(0x80 | $c & 0x3F);

}

else if ($c < 0x10000) {

$str.=chr(0xE0 | $c>>12);

$str.=chr(0x80 | $c>>6 & 0x3F);

$str.=chr(0x80 | $c & 0x3F);

}

else if ($c < 0x200000) {

$str.=chr(0xF0 | $c>>18);

$str.=chr(0x80 | $c>>12 & 0x3F);

$str.=chr(0x80 | $c>>6 & 0x3F);

$str.=chr(0x80 | $c & 0x3F);

}

return $str;

}

?>

--------------------------------------------

<?

Header ("Content-type: image/jpeg");

$im = imagecreate (800, 400);

$black = ImageColorAllocate ($im, 0, 0, 0);

$white = ImageColorAllocate ($im, 255, 255, 255);

include("gb2utf8.php");

$str=gb2utf8("aaa中过32434");

ImageTTFText ($im, 90, 10, 110, 300, $white, "/usr/share/fonts/default/TrueType/simsun.ttc",

$str);

ImageJPEG ($im);

ImageDestroy ($im);

?>