我有代码在我的本地机器上显示验证码。但是，当我将该代码放入服务器时，验证码图像无法正常工作。请任何人解决我的问题。我的本地机器是ubuntu 12.04，服务器机器是ubuntu 14.04。以下是我的代码。
demo.php
<?php session_start();
if(isset($_POST['Submit'])){
// code for check server side validation
if(empty($_SESSION['captcha_code'] ) || strcasecmp($_SESSION['captcha_code'], $_POST['captcha_code']) != 0){
$msg="<span style='color:red'>The Validation code does not match!</span>";// Captcha verification is incorrect.
}else{// Captcha verification is Correct. Final Code Execute here!
$msg="<span style='color:green'>The Validation code has been matched.</span>";
}
}
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>PHP Secure Professional Captcha.</title>
<link href="./css/stylecaptcha.css" rel="stylesheet">
<script type='text/javascript'>
function refreshCaptcha(){
var img = document.images['captchaimg'];
img.src = img.src.substring(0,img.src.lastIndexOf("?"))+"?rand="+Math.random()*1000;
}
</script>
</head>
<body>
<br>
<form action="" method="post" name="form1" id="form1" >
<table width="400" border="0" align="center" cellpadding="5" cellspacing="1" class="table">
<?php if(isset($msg)){?>
<tr>
<td colspan="2" align="center" valign="top"><?php echo $msg;?></td>
</tr>
<?php } ?>
<tr>
<td align="right" valign="top"> Validation code:</td>
<td><img src="captcha.php?rand=<?php echo rand();?>" id='captchaimg'><br>
<label for='message'>Enter the code above here :</label>
<br>
<input id="captcha_code" name="captcha_code" type="text">
<br>
Cannot read the image? click <a href='javascript: refreshCaptcha();'>here</a> to refresh.</td>
</tr>
<tr>
<td> </td>
<td><input name="Submit" type="submit" onclick="return validate();" value="Submit" class="button1"></td>
</tr>
</table>
</form>
</body>
</html>
captcha.php
<?php
session_start();
include("./phptextClass.php");
/*create class object*/
$phptextObj = new phptextClass();
/*phptext function to genrate image with text*/
$phptextObj->phpcaptcha('#162453','#fff',120,40,10,25);
?>
phptextClass.php
<?php
/*phptext class, version 1.0
created by www.w3schools.in (Gautam kumar)
April 26, 2014
*/
class phptextClass
{
public function phptext($text,$textColor,$backgroundColor='',$fontSize,$imgWidth,$imgHeight,$dir,$fileName)
{
/* settings */
$font = './calibri.ttf';/*define font*/
$textColor=$this->hexToRGB($textColor);
$im = imagecreatetruecolor($imgWidth, $imgHeight);
$textColor = imagecolorallocate($im, $textColor['r'],$textColor['g'],$textColor['b']);
if($backgroundColor==''){/*select random color*/
$colorCode=array('#56aad8', '#61c4a8', '#d3ab92');
$backgroundColor = $this->hexToRGB($colorCode[rand(0, count($colorCode)-1)]);
$backgroundColor = imagecolorallocate($im, $backgroundColor['r'],$backgroundColor['g'],$backgroundColor['b']);
}else{/*select background color as provided*/
$backgroundColor = $this->hexToRGB($backgroundColor);
$backgroundColor = imagecolorallocate($im, $backgroundColor['r'],$backgroundColor['g'],$backgroundColor['b']);
}
imagefill($im,0,0,$backgroundColor);
list($x, $y) = $this->ImageTTFCenter($im, $text, $font, $fontSize);
imagettftext($im, $fontSize, 0, $x, $y, $textColor, $font, $text);
if(imagejpeg($im,$dir.$fileName,90)){/*save image as JPG*/
return json_encode(array('status'=>TRUE,'image'=>$dir.$fileName));
imagedestroy($im);
}
}
public function phpcaptcha($textColor,$backgroundColor,$imgWidth,$imgHeight,$noiceLines=0,$noiceDots=0,$noiceColor='#000000')
{
/* Settings */
$text=$this->random();
$font = './font/monofont.ttf';/* font */
$textColor=$this->hexToRGB($textColor);
$fontSize = $imgHeight * 0.75;
$im = imagecreatetruecolor($imgWidth, $imgHeight);
$textColor = imagecolorallocate($im, $textColor['r'],$textColor['g'],$textColor['b']);
$backgroundColor = $this->hexToRGB($backgroundColor);
$backgroundColor = imagecolorallocate($im, $backgroundColor['r'],$backgroundColor['g'],$backgroundColor['b']);
/* generating lines randomly in background of image */
if($noiceLines>0){
$noiceColor=$this->hexToRGB($noiceColor);
$noiceColor = imagecolorallocate($im, $noiceColor['r'],$noiceColor['g'],$noiceColor['b']);
for( $i=0; $i<$noiceLines; $i++ ) {
imageline($im, mt_rand(0,$imgWidth), mt_rand(0,$imgHeight),
mt_rand(0,$imgWidth), mt_rand(0,$imgHeight), $noiceColor);
}}
if($noiceDots>0){/* generating the dots randomly in background */
for( $i=0; $i<$noiceDots; $i++ ) {
imagefilledellipse($im, mt_rand(0,$imgWidth),
mt_rand(0,$imgHeight), 3, 3, $textColor);
}}
imagefill($im,0,0,$backgroundColor);
list($x, $y) = $this->ImageTTFCenter($im, $text, $font, $fontSize);
imagettftext($im, $fontSize, 0, $x, $y, $textColor, $font, $text);
imagejpeg($im,NULL,90);/* Showing image */
header('Content-Type: image/jpeg');/* defining the image type to be shown in browser widow */
imagedestroy($im);/* Destroying image instance */
if(isset($_SESSION)){
$_SESSION['captcha_code'] = $text;/* set random text in session for captcha validation*/
}
}
/*for random string*/
protected function random($characters=6,$letters = '23456789bcdfghjkmnpqrstvwxyz'){
$str='';
for ($i=0; $i<$characters; $i++) {
$str .= substr($letters, mt_rand(0, strlen($letters)-1), 1);
}
return $str;
}
/*function to convert hex value to rgb array*/
protected function hexToRGB($colour)
{
if ( $colour[0] == '#' ) {
$colour = substr( $colour, 1 );
}
if ( strlen( $colour ) == 6 ) {
list( $r, $g, $b ) = array( $colour[0] . $colour[1], $colour[2] . $colour[3], $colour[4] . $colour[5] );
} elseif ( strlen( $colour ) == 3 ) {
list( $r, $g, $b ) = array( $colour[0] . $colour[0], $colour[1] . $colour[1], $colour[2] . $colour[2] );
} else {
return false;
}
$r = hexdec( $r );
$g = hexdec( $g );
$b = hexdec( $b );
return array( 'r' => $r, 'g' => $g, 'b' => $b );
}
/*function to get center position on image*/
protected function ImageTTFCenter($image, $text, $font, $size, $angle = 8)
{
$xi = imagesx($image);
$yi = imagesy($image);
$box = imagettfbbox($size, $angle, $font, $text);
$xr = abs(max($box[2], $box[4]));
$yr = abs(max($box[5], $box[7]));
$x = intval(($xi - $xr) / 2);
$y = intval(($yi + $yr) / 2);
return array($x, $y);
}
}
?>