Php verification code

Php implements the verification code function. the verification code function is everywhere. next we use php to implement the verification code function. here we extract the verification code into a class, if you use the verification code function later, you can directly introduce this type of file and create an instance of this type, you can use the verification code as follows:

Verification code file vcode. class. php

 Width = $ width; $ this-> height = $ height; $ this-> num = $ num; $ this-> code = $ this-> createCode (); $ this-> pointnum= 100; $ this-> lineNum = 10; $ this-> fontFile = "STLITI. TTF ";}/*** is used to set member attributes * @ param string $ key member attribute name * @ param mixed $ value member attribute value * @ return object returns its own object $ this, it can be used for coherent operations */public function set ($ key, $ val) {// get_class_vars () to obtain an array composed of attributes in the class // get_class () returned object class name if (array_key_exists ($ key, get_class_vars (get_class ($ this) {$ this-> setOption ($ key, $ val );} return $ this;} // Set the private function setOption ($ key, $ value) {$ this-> $ key = $ value;} // Obtain the verification code public function getCode () {return $ this-> code;} // output Image public function outImg () {// create image $ this-> createImage (); // draw verification code $ this-> drawCode (); // draw interference elements $ this-> drawDisturbColor (); // output image $ this-> printImg ();} // draw the verification code private function drawCode () {$ this-> fontFile = ". /font /". $ this-> fontFile; for ($ I = 0; $ I <$ this-> num; $ I ++) {// Set the random color $ randColor = imagecolorallocate ($ this-> img, rand (0,128), rand (0,128), rand (0,128 )); // font size $ fontSize = rand (20, 23); // font horizontal position $ x = ($ this-> width/$ this-> num) * $ I; // horizontal position $ y = rand ($ fontSize, imagefontheight ($ fontSize) + 3); // draw the font imagettftext ($ this-> img, $ fontSize, 0, $ x, $ y, $ randColor, $ this-> fontFile, $ this-> code {$ I}) ;}// draw interference element private function drawDisturbColor () {// draw interference points for ($ I = 0; $ I <$ this-> pointNum; $ I ++) {// Set the random color $ randColor = imagecolorallocate ($ this-> img, rand (0,255), rand (0,255), rand (0,255 )); // Image point imagesetpixel ($ this-> img, rand (1, $ this-> width-2), rand (1, $ this-> height-2 ), $ randColor);} // draw the interference line for ($ I = 0; $ I <$ this-> lineNum; $ I ++) {// Set the random color $ randColor = imagecolorallocate ($ this-> img, rand (0,200), rand (0,200), rand (0,200 )); // draw line imageline ($ this-> img, rand (1, $ this-> width-2), rand (1, $ this-> height-2 ), rand (1, $ this-> height-2), rand (1, $ this-> width-2), $ randColor );}} // create an image private function createImage () {// create a true color image $ this-> img = imagecreatetruecolor ($ this-> width, $ this-> height ); // set the background color $ bgColor = imagecolorallocate ($ this-> img, rand (200,255), rand (200,255), rand (200,255 )); // fill in the background color imagefill ($ this-> img, $ bgColor); // set the border color $ borderColor = imagecolorallocate ($ this-> img, 0 ); // draw a border imagerectangle ($ this-> img, 0, $ this-> width-1, $ this-> height-1, $ borderColor );} // output image private function printImg () {if (imagetypes () & IMG_PNG) {// for pngheader ("Content-Type: image/png "); imagepng ($ this-> img);} else if (imagetypes () & IMG_JPG) {// for jpgheader ("Content-Type: image/jpeg "); imagejpeg ($ this-> img, null, 100);} else if (imagetypes () & IMG_GIF) {// for Gifheader ("Content-Type: image/gif "); imagegif ($ this-> img);} else if (imagetypes () & IMG_WBMP) {// for WBMPheader ('content-Type: image/vnd. wap. wbmp '); imagewbmp ($ this-> img);} else {die ('No image support in this PHP server'); }}// create a verification code private function createCode () {// Default string $ codes = "123456789 abcdefghijkmnpqrstuvwxyABCDEFGHIJKLMNOPQRSTUVWXY"; // Generate a verification code $ code = ""; for ($ I = 0; $ I <$ this-> num; $ I ++) {$ code. = $ codes {rand (0, strlen ($ codes)-1) };}return $ code;} // destructor used to destroy Image resources function _ destruct () {imagedestroy ($ this-> img );}}

Here, the function used to draw fonts is imagettftext (), because this function can customize the font style. it can be seen from the code that the passed parameters have a font file attribute, if you do not like this function, you can use the imagestring () function, but I personally think the default font size of this function is not good. Or the custom font looks more comfortable. Next we will call the verification code class.

 GetCode (); // $ vcode-> set ("pointNum", 10); // number of custom interference points // $ vcode-> set ("lineNum ", 10); // number of custom interference lines // $ vcode-> set ("fontFile", "wawa. ttf "); // custom font file // output image $ vcode-> outImg ();

The verification code is implemented here. you can also view the verification code by directly calling this file. the following uses a simple logon form to use this verification code.

 Alert ('verification code is correct! '); Script ";} else {echo"