PHP verification code implements partial refresh_PHP tutorial-PHP Tutorial-php.cn

Generally when using verification codes, we have to implement partial refresh. This is inevitable and is also a point to improve user experience. Let’s take a look at the usage of PHP verification codes in practical applications. Friends in need can refer to it. one time.

/*
* Auth_code() is the verification code function
* @access public
* @param int $width represents the length of the verification code, the default is 80
* @param int $height represents the height of the verification code, the default is 20
* @param int $num represents the number of digits in the verification code, the default is 4
* @param int $line represents the number of lines in the verification code, the default is 4
* @param int $line represents the number of midpoints in the verification code, the default is 150
*/

//Get color

The code is as follows

代码如下

复制代码

function Auth_code($width = 80,$height = 20,$num = 4,$line = 4,$dot = 150) {

$length = floor($width/$num); //floor:取整数部分 length:每段平均长度
for($i=0;$i<$num;$i++)
@$rand.=dechex(mt_rand(1,15));
$_SESSION['code']=$rand;

//新建一个黑色底的画板
$im=imagecreatetruecolor($width,$height);

//取色
$green=imagecolorallocate($im,0,255,0);
$red = imagecolorallocate($im,255,0,0);
$white=imagecolorallocate($im,255,255,255);
$black = imagecolorallocate($im,0,0,0);

//填充画板
//imagefill($im,0,0,$green);

//画线
for($i=0;$i<$line;$i++){
$color=imagecolorallocate($im,rand(0,255),rand(0,255),rand(0,255));
imageline($im,rand(10,$width-10),0,rand(0,$width),$height,$color);
}
//画点
for($i=0;$i<$dot;$i++){
$color=imagecolorallocate($im,rand(0,255),rand(0,255),rand(0,255));
imagesetpixel($im,rand(0,$width),rand(0,$height),$color);
}
//画数字
for($i=0;$i<$num;$i++) {
imagestring($im,5,mt_rand($i*$length+1,($i+1)*$length-8),mt_rand(0,$height-14),$_SESSION['code'][$i],$white);
}

//输出图片
header("content-type:image/jpeg");
imagejpeg($im);
}

Copy code

function Auth_code($width = 80,$height = 20,$num = 4,$line = 4,$dot = 150) {

$length = floor($width/$num); //floor: take the integer part length: the average length of each segment
for($i=0;$i<$num;$i++)
@$rand.=dechex(mt_rand(1,15));
$_SESSION['code']=$rand;

//Create a new drawing board with a black background

代码如下	复制代码

$im=imagecreatetruecolor($width,$height);

$green=imagecolorallocate($im,0,255,0); $red = imagecolorallocate($im,255,0,0); $white=imagecolorallocate($im,255,255,255); $black = imagecolorallocate($im,0,0,0); //Fill the artboard //imagefill($im,0,0,$green); //Draw line for($i=0;$i<$line;$i++){<🎜> $color=imagecolorallocate($im,rand(0,255),rand(0,255),rand(0,255));<🎜> imageline($im,rand(10,$width-10),0,rand(0,$width),$height,$color);<🎜> }<🎜> //Draw dots<🎜> for($i=0;$i<$dot;$i++){<🎜> $color=imagecolorallocate($im,rand(0,255),rand(0,255),rand(0,255));<🎜> imagesetpixel($im,rand(0,$width),rand(0,$height),$color);<🎜> }<🎜> //Draw numbers<🎜> for($i=0;$i<$num;$i++) { <🎜> imagestring($im,5,mt_rand($i*$length+1,($i+1)*$length-8),mt_rand(0,$height-14),$_SESSION['code'][$i ],$white);<🎜> }<🎜> <🎜> //Output picture<🎜> header("content-type:image/jpeg");<🎜> imagejpeg($im);<🎜> }<🎜> <🎜> <🎜> <🎜> <🎜> - Main function: <🎜> imagecreatetruecolor //Create a new drawing board with a black background<🎜> imagecolorallocate //Get color<🎜> imagefill imagefill //Fill the artboard<🎜> imageline imageline //Draw a line<🎜> imagesetpixel //Draw points<🎜> imagestring imagestring //Draw a string (this verification code is a number)<🎜> Note: When drawing the digital verification code on the drawing board, please pay attention to the font out of bounds, so you need to subtract some range accordingly. See the attachment for details. <🎜> -Partial refresh verification code: <🎜>

The code is as follows<🎜>

Copy code<🎜> <🎜>

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source：php.cn

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