使用 php 将 imagestring() 居中？

Question

我正在尝试为我的欢迎页面创建一个图像，并希望将字符串动态居中，否则使用不同的用户名（例如 John 和 Alexandra）就太糟糕了。

header("Content-type: image/png");

$string1 = "Hello!";
$string2 = "Welcome to our website!";
$srting3 = "$username";

$font1  = 5;
$font2  = 3;
$font3  = 3;

$img_w = 240;
$img_h =  64;

$image = imagecreatetruecolor ($img_w, $img_h);
$white = imagecolorallocate   ($image, 255,255,255);
$black = imagecolorallocate   ($image,   0,  0,  0);
imagefill($image, 0, 0, $white);

imagestring ($image, $font1, 110,  0, $string1, $black);
imagestring ($image, $font2,  60, 20, $string2, $black);
imagestring ($image, $font3, 105, 40, $string3, $black);

imagepng ($image);
imagedestroy($image);

Answer 1

Tryimagefontwidth()函数获取每个字符的宽度并将其相乘，strlen($string)您也可以使用imagefontheight()来更新高度。

header("Content-type: image/png");

$string1 = "Hello!";
$string2 = "Welcome to our website!";
$srting3 = "$username";

$font1  = 5;
$width1 = imagefontwidth($font1) * strlen($string);
$height1 = imagefontheight($font1);

$font2  = 3;
$width2 = imagefontwidth($font2) * strlen($string2);
$height2 = imagefontheight($font2);

$font3  = 3;
$width3 = imagefontwidth($font3) * strlen($string3);
$height3 = imagefontheight($font3);

$img_w = 240;
$img_h = 64;

$image = imagecreatetruecolor ($img_w,$img_h);
$white = imagecolorallocate ($image,255,255,255);
$black = imagecolorallocate ($image,0,0,0);
imagefill($image,0,0,$white);

imagestring ($image,$font1,($img_w/2)-($width1/2),        0,$string1,$black);
imagestring ($image,$font2,($img_w/2)-($width2/2), $height1,$string2,$black);
imagestring ($image,$font3,($img_w/2)-($width3/2), $height1+$height2,$string3,$black);


imagepng ($image);
imagedestroy($image);