<?php

$img = imagecreatetruecolor(200, 200);

$red = imagecolorallocate($img, 0xFF, 0x00, 0x00);

$blue = imagecolorallocate($img,0x00,0x44,0xff);

//在这里使用imageline绘制线条

imageline($img,0,200,200,0,$red);

imageline($img,200,100,0,100,$blue);

imageline($img,100,200,100,0,$blue);

imageline($img,200,200,0,0,$red);

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

imagepng($img);

imagedestroy($img);