PHP Verification Code Class code (latest modification, fully customized!)

Authnum.class.php Download
Copy CodeThe code is as follows:
<?php
Session_Start ();
Class Authnum {
Picture object, width, height, verification code length
Private $im;
Private $im _width;
Private $im _height;
Private $len;
Random string, y coordinate value, random color
Private $randnum;
Private $y;
Private $randcolor;
The background color is red, green and blue, the default is light gray
Public $red = 238;
Public $green = 238;
Public $blue = 238;
/**
* Optional Settings: Authentication code type, interference point, interference line, y-axis random
* Set to False to not enable
**/
The default is a combination of uppercase and lowercase numbers, 1 2 3 for small, upper-case, and numeric
Public $ext _num_type= ';
Public $ext _pixel = false; Jamming Point
Public $ext _line = false; Jamming line
Public $ext _rand_y= true; Y-Axis random
function __construct ($len =4, $im _width= ', $im _height=25) {
Verification code length, picture width, height is the data that is required to instantiate the class
$this->len = $len; $im _width = $len * 15;
$this->im_width = $im _width;
$this->im_height= $im _height;
$this->im = imagecreate ($im _width, $im _height);
}
Set picture background color, default is light gray background
function Set_bgcolor () {
Imagecolorallocate ($this->im, $this->red, $this->green, $this->blue);
}
Random code to obtain arbitrary digit number
function Get_randnum () {
$an 1 = ' abcdefghijklmnopqrstuvwxyz ';
$an 2 = ' abcdefghijklmnopqrstuvwxyz ';
$an 3 = ' 0123456789 ';
if ($this->ext_num_type = = ") $str = $an 1. $an 2. $an 3;
if ($this->ext_num_type = = 1) $str = $an 1;
if ($this->ext_num_type = = 2) $str = $an 2;
if ($this->ext_num_type = = 3) $str = $an 3;
for ($i = 0; $i < $this->len; $i + +) {
$start = rand (1,strlen ($STR)-1);
$randnum. = substr ($str, $start, 1);
}
$this->randnum = $randnum;
$_session[an] = $this->randnum;
}
Get Verification code Picture Y axis
function get_y () {
if ($this->ext_rand_y) $this->y = rand (5, $this-&GT;IM_HEIGHT/5);
else $this->y = $this-&GT;IM_HEIGHT/4;
}
Get random Color
function Get_randcolor () {
$this->randcolor = imagecolorallocate ($this->im,rand (0,100), Rand (0,150), Rand (0,200));
}
Add interference points
function Set_ext_pixel () {
if ($this->ext_pixel) {
for ($i = 0; $i < $i + +) {
$this->get_randcolor ();
Imagesetpixel ($this->im, rand ()%100, Rand ()%100, $this->randcolor);
}
}
}
Add interference Line
function Set_ext_line () {
if ($this->ext_line) {
for ($j = 0; $j < 2; $j + +) {
$rand _x = rand (2, $this->im_width);
$rand _y = rand (2, $this->im_height);
$rand _x2 = rand (2, $this->im_width);
$rand _y2 = rand (2, $this->im_height);
$this->get_randcolor ();
Imageline ($this->im, $rand _x, $rand _y, $rand _x2, $rand _y2, $this->randcolor);
}
}
}
/** Create a CAPTCHA Image:
* Create canvas (__construct function)
* Set Canvas background ($this->set_bgcolor ();)
* Get a random string ($this->get_randnum ();)
* Writing to the picture (imagestring function)
* Add interference point/Line ($this->set_ext_line (); $this->set_ext_pixel ();
* Output Picture
**/
function Create () {
$this->set_bgcolor ();
$this->get_randnum ();
for ($i = 0; $i < $this->len; $i + +) {
$font = rand (4,6);
$x = $i/$this->len * $this->im_width + rand (1, $this->len);
$this->get_y ();
$this->get_randcolor ();
Imagestring ($this->im, $font, $x, $this->y, substr ($this->randnum, $i, 1), $this->randcolor);
}
$this->set_ext_line ();
$this->set_ext_pixel ();
Header ("Content-type:image/png");
Imagepng ($this->im);
Imagedestroy ($this->im); Releasing image resources
}
}//end class
/** methods for using the Authentication code class:
* $an = new Authnum (Verification code length, picture width, picture height);
* Instantiated with no parameters, the default is four-bit 60*25 size of the general verification Code picture
* Form page Detection Verification code method, contrast $_session[an] is equal to $_post[captcha text box ID]
* Optional Configuration:
* 1 Authentication code type: $an->ext_num_type=1; A value of 1 is a lowercase type, 2 is an uppercase type, and 3 is a numeric type
* 2. Jamming point: $an->ext_pixel = false; A value of false indicates no interference point added
* 3. Interference line: $an->ext_line = false; A value of false indicates no interference lines added
* 4.Y Axis random: $an->ext_rand_y = false; A value of false indicates that the picture y-axis is not supported randomly
* 5. Picture background: Change $red $green $blue The value of three member variables
**/
$an = new Authnum ();
$an->ext_num_type= ';
$an->ext_pixel = true; Jamming Point
$an->ext_line = false; Jamming line
$an->ext_rand_y= true; Y-Axis random
$an->green = 238;
$an->create ();
?>