


Complete code of PHP verification code generation class_PHP tutorial
This article provides this PHP verification code generation class that is flexible and easy to use. Users can define each member to have width, height, canvas, number of words, type, and painting type. At the same time, we only need to modify $Type to define that the generated ones are pure numbers and pure lowercase letters. , mixed uppercase and lowercase numbers, friends in need can refer to it.
The code is as follows
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Copy code | ||||
private $height; //Height
private $num; //Number of verification code words
private $imgType; //Generate image type
private $Type ; //String type 1, 2, 3 three options 1 Pure numbers 2 Pure lowercase letters 3 Mixed uppercase and lowercase numbers
private $hb; //Canvas
public $codestr; // Verification code word Stringpublic function __construct($height=20,$num=4,$imgType="jpeg",$Type=1){
$this->width = $num*20 ;
$this->height = $height;
$this->num = $num;
$this->imgType = $imgType;
$this- >Type = $Type;
$this->codestr = $this->codestr();
$this->zuhe();
}// 2. Define a random string function
private function codestr(){
switch($this->Type){case 1: // The type is 1 Get random numbers 1-9
$str = implode("",array_rand(range(0,9),$this->num));
break;
case 2: //Type 2 gets a-z random lowercase letters
$str = implode("",array_rand(array_flip(range(a,z)),$this->num));
break;case 3: // Type 3 gets mixed numbers, lowercase letters, and uppercase letters
for($i=0;$inum;$i++){
$ m = rand(0,2);
switch($m){
case 0:
$o = rand(48,57);
break;
case 1:
$o = rand(65,90);
break;
case 2:
$o = rand(97,122);
break;
/>}
$str .= sprintf("%c",$o);
}
break;
}
return $str;
}
// 3. Initialize the canvas image resource
private function Hb(){
$this->hb = imagecreatetruecolor( $this->width,$this->height);
}// 4. Generate background color
private function Bg(){
return imagecolorallocate ($this->hb,rand(130,250),rand(130,250),rand(130,250));
}// 5. Generate font color
private function Font (){
return imagecolorallocate($this->hb,rand(0,100),rand(0,100),rand(0,100));
}// 6. Fill Background color
private function BgColor(){
imagefilledrectangle($this->hb,0,0,$this->width,$this->height,$this->Bg( ));
}// 7. Interference points
private function ganrao(){
$sum=floor(($this->width)*( $this->height)/3);
for($i=0;$iimagesetpixel($this->hb,rand(0,$ this->width),rand(0,$this->height),$this->Bg());
}
}// 8. Random straight line arc
private function huxian(){
for($i=0;$inum;$i++){
imageArc($this-> hb,rand(0,$this->width),rand(0,$this->height),rand(0,$this->width),rand(0,$this->height), rand(0,360),rand(0,360),$this->Bg());
}
}// 9. Writing
private function xiezi( ){
for($i=0;$inum;$i++){
$x=ceil($this->width/$this->num) *$i;
$y=rand(1,$this->height-15);
imagechar($this->hb,5,$x+4,$y,$this ->codestr[$i],$this->Font());
}
}// 10. Output
private function OutImg() {
$shuchu="image".$this->imgType;
$header="Content-type:image/".$this->imgType;
if(function_exists( $shuchu)){
header($header);
$shuchu($this->hb);
}else{
exit("There is no such image in the GD library ");
}
}// 11. Assembly
private function zuhe(){
$this->Hb();
$this->BgColor();
$this->ganrao();
$this->huxian();
$this->xiezi();
$this->OutImg();
}public function getCodeStr(){
return $this->codestr;
}
}
?>

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