php - 在 php 中检查同一页面上的验证码

Question

我正在从用户输入一个表单，该表单在提交时调用一个javascript函数并检查是否填写了强制条目。如果是这样，它会转到另一个文件。现在我正在另一个文件中检查这个验证码。我怎么能在同一页面上这样做？先感谢您！

Answer 1

验证码生成代码

验证码.php：

$string = '';
for ($i = 0; $i < 5; $i++) // 5 -is considered here as the length of string
    $string .= chr(rand(97, 122));
$_SESSION['captcha']=$string;   // stores to session 
$image = imagecreatetruecolor(110, 28);
$fontArray[0]="a4.ttf";$fontArray[1]="a5.ttf";$fontArray[2]="a1.ttf";$fontArray[3]="a4.ttf";
// just a font array for diff look Note : try ttf
$font = 'font/'.$fontArray[rand()%3]; // selecting random font
$color = imagecolorallocate($image, 255, 255, 255);// color
$background = imagecolorallocate($image, 0, 0, 0); // background color
$grey = imagecolorallocate($image, 180, 180, 180);//shadow color
imagefilledrectangle($image,0,0,399,99,$background);
imagettftext($image, 18, 0, 11, 23, $grey, $font, $string);//shadow of the text
imagettftext($image, 18, 0, 10, 22, $color, $font, $string);// text
//Actual function array imagettftext ( resource $image , float $size , float $angle , int $x , int $y , int $color , string $fontfile , string $text )
header("Content-type: image/png");
imagepng($image);

然后将其用作显示页面中的图像。喜欢 -

<img id="capcaptcha" src="captcha.php" />
<a onclick="new_capcaptcha()">Click here to reload captha</a>

jQuery

function new_capcaptcha(){
    $('#capcaptcha').attr('src','');
    $('#capcaptcha').attr('src','captcha.php?rand='+Math.random());
    // to avoid browser cache passed 'rand'
    } 

对于验证，您可以使用先前存储的会话变量 $_SESSION['captcha']

希望这会有所帮助

Answer 2

一个简单的 PHP 验证码脚本

<?php

session_start();
include("captcha.php");
$_SESSION['captcha'] = captcha();

echo '<img src="' . $_SESSION['captcha']['image_src'] . '" alt="CAPTCHA" />';

?>

更多- http://www.abeautifulsite.net/blog/2011/01/a-simple-php-captcha-script/

Answer 3

验证码生成器 -

<?php 
session_start();
//Settings: You can customize the captcha here
$image_width = 200;
$image_height = 60;
$characters_on_image = 5;
$font = './monofont.ttf';

//The characters that can be used in the CAPTCHA code.
//avoid confusing characters (l 1 and i for example)
$possible_letters = '23456789bcdfghjkmnpqrstvwxyz';
$random_dots = 140;
$random_lines = 5;
$captcha_text_color="0x142864";
$captcha_noice_color = "0x142864";

$code = '';


$i = 0;
while ($i < $characters_on_image) { 
$code .= substr($possible_letters, mt_rand(0, strlen($possible_letters)-1), 1);
$i++;
}


$font_size = $image_height * 0.75;
$image = @imagecreate($image_width, $image_height);


/* setting the background, text and noise colours here */
$background_color = imagecolorallocate($image, 255, 255, 255);

$arr_text_color = hexrgb($captcha_text_color);
$text_color = imagecolorallocate($image, $arr_text_color['red'], 
        $arr_text_color['green'], $arr_text_color['blue']);

$arr_noice_color = hexrgb($captcha_noice_color);
$image_noise_color = imagecolorallocate($image, $arr_noice_color['red'], 
        $arr_noice_color['green'], $arr_noice_color['blue']);


/* generating the dots randomly in background */
for( $i=0; $i<$random_dots; $i++ ) {
imagefilledellipse($image, mt_rand(0,$image_width),
 mt_rand(0,$image_height), 2, 3, $image_noise_color);
}


/* generating lines randomly in background of image */
for( $i=0; $i<$random_lines; $i++ ) {
imageline($image, mt_rand(0,$image_width), mt_rand(0,$image_height),
 mt_rand(0,$image_width), mt_rand(0,$image_height), $image_noise_color);
}


/* create a text box and add 6 letters code in it */
$textbox = imagettfbbox($font_size, 0, $font, $code); 
$x = ($image_width - $textbox[4])/2;
$y = ($image_height - $textbox[5])/2;
imagettftext($image, $font_size, 0, $x, $y, $text_color, $font , $code);


/* Show captcha image in the page html page */
header('Content-Type: image/jpeg');// defining the image type to be shown in browser widow
imagejpeg($image);//showing the image
imagedestroy($image);//destroying the image instance
$_SESSION['6_letters_code_1'] = $code;

function hexrgb ($hexstr)
{
  $int = hexdec($hexstr);

  return array("red" => 0xFF & ($int >> 0x10),
               "green" => 0xFF & ($int >> 0x8),
               "blue" => 0xFF & $int);
}
?>

您还可以从 www.uandblog.com ( http://www.uandblog.com/How-to-Create-Captcha-Code-using-PHP )获取详细信息