用GD或任何其他库显示带下划线的文本并将结果输出为图像的最佳方法是什么？

解决方法:

您可以尝试使用结合了字符U 0332的Unicode下划线.

<?php
// Set the content-type
header('Content-type: image/png');

// Create the image
$im = imagecreatetruecolor(400, 30);

// Create some colors
$white = imagecolorallocate($im, 255, 255, 255);
$black = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 399, 29, $white);

// The text to draw
$text = "&#x0332;U&#x0332;d&#x0332;e&#x0332;r&#x0332;l&#x0332;i&#x0332;n&#x0332;e";
// Replace path by your own font path
$font = 'arial.ttf';


// Add the text
imagettftext($im, 20, 0, 10, 20, $black, $font, $text);

// Using imagepng() results in clearer text compared with imagejpeg()
imagepng($im);
imagedestroy($im);
?>