PHP drawing function generates image verification code

PHP drawing function generates image verification code

  Set some important CAPTCHA constantsDefine' Captcha_numchars ',6);// number of characters in Pass-phraseDefine' Captcha_width ', -);//width of imageDefine' Captcha_height ', -);//height of image//Generate the random pass-phrase$pass _phrase=""; for($i=0;$i< Captcha_numchars;$i++) {$pass _phrase. = Chr (Rand( the,122)); }//Store The encrypted pass-phrase in a session variable$_session[' Pass_phrase '] = SHA ($pass _phrase);//Create the image$img= Imagecreatetruecolor (Captcha_width, captcha_height);//Set a white background with black text and gray graphics$BG _color= Imagecolorallocate ($img,255,255,255);// White$text _color= Imagecolorallocate ($img,0,0,0);//Black$graphic _color= Imagecolorallocate ($img, -, -, -);//Dark gray//Fill the backgroundImagefilledrectangle ($img,0,0, Captcha_width, Captcha_height,$BG _color);//Draw some random lines for($i=0;$i<5;$i+ +) {Imageline ($img,0,Rand()% Captcha_height, Captcha_width,Rand()% Captcha_height,$graphic _color); }//Sprinkle in some random dots for($i=0;$i< -;$i+ +) {Imagesetpixel ($img,Rand()% Captcha_width,Rand()% Captcha_height,$graphic _color); }//Draw the Pass-phrase stringImagettftext ($img, -,0,5, Captcha_height-5,$text _color,' Courier New bold.ttf ',$pass _phrase);//Output the image as a PNG using a headerHeader"Content-type:image/png"); Imagepng ($img);// clean upImagedestroy ($img);? >

Use this script to generate the CAPTCHA in the page

  
      session_start ();? >
  <htmlxmlns="http://www.w3.org/1999/xhtml"xml: Lang="en"lang="en"><head>< Meta http-equiv= "content-type"Content="text/html; Charset=utf-8 " /><title>Guitar wars-add Your high score 
      title< /c24>>
  <linkrel="stylesheet"type="text/css"href ="Style.css" /> 
     Head
 ><body><h2>Guitar Wars-add Your High Score 
     H2
 >
    require_once(' appvars.php ');require_once(' connectvars.php ');if(isset($_post[' Submit '])) {//Connect to the database$dbc= Mysqli_connect (Db_host, Db_user, Db_password, db_name);//Grab The score data from the POST$name= Mysqli_real_escape_string ($dbc, Trim ($_post[' name ']));$score= Mysqli_real_escape_string ($dbc, Trim ($_post[' score ']));$screenshot= Mysqli_real_escape_string ($dbc, Trim ($_files[' screenshot '][' name ']));$screenshot _type=$_files[' screenshot '][' type '];$screenshot _size=$_files[' screenshot '][' Size '];//Check The CAPTCHA pass-phrase for verification$user _pass_phrase= SHA ($_post[' Verify ']);if($_session[' Pass_phrase '] ==$user _pass_phrase) {if(!Empty($name) && Is_numeric ($score) &&!Empty($screenshot)) {if((($screenshot _type==' Image/gif ') || ($screenshot _type==' Image/jpeg ') || ($screenshot _type==' Image/pjpeg ') || ($screenshot _type==' Image/png ')) && ($screenshot _size>0) && ($screenshot _size<= gw_maxfilesize)) {if($_files[' screenshot '][' ERROR '] ==0) {//Move the file to the target upload folder$target= Gw_uploadpath.$screenshot;if(Move_uploaded_file ($_files[' screenshot '][' Tmp_name '],$target)) {//Write The data to the database$query="INSERT into Guitarwars (date, name, score, screenshot) VALUES (now (), ' $name ', ' $score ', ' $screenshot ')"; Mysqli_query ($dbc,$query);//Confirm success with the userEcho'
Thanks for adding your new high score! It is reviewed and added to the high score list as soon as possible.
';Echo'
Name: ' . $name . '

        '; Echo 'score: ' . $score . '

        '; Echo ' . Gw_uploadpath. $screenshot . ' "alt=" PHP drawing function generates a picture verification code "/> 
';Echo'
<< back to high scores
';//Clear the score data to clear the form$name="";$score="";$screenshot=""; Mysqli_close ($dbc); }Else{Echo'
Sorry, there is a problem uploading your screen shot image.
'; }          }        }Else{Echo'
The screen shot must is a GIF, JPEG, or PNG image file no greater than '. (Gw_maxfilesize/ 1024x768). ' KB in size.
'; }//Try to delete the temporary screen shot image file@unlink ($_files[' screenshot '][' Tmp_name ']); }Else{Echo'
Please enter any of the information to add your high score.
'; }    }Else{Echo'
Please enter the verification pass-phrase exactly as shown.
'; }  }?><hr /><formenctype= "multipart/form-data"method="POST"  Action=" 
       "><inputtype="hidden"name="max_file_size"  Value=" 
       " /><labelfor ="name">Name: 
      Label
 ><inputtype="text"id="Name"name=" name" Value=" 
      " /><br /><labelfor ="Score">Score: 
     Label
 ><inputtype="text"id="Score"name= "Score" Value=" 
      " /><br /><labelfor ="screenshot">Screen shot: 
     Label
 ><inputtype="file"id="screenshot"name=" Screenshot " /><br /><labelfor ="Verify">Verification: 
     Label
 ><inputtype="text"id="Verify"name= "Verify" Value="Enter the pass-phrase." /><imgsrc="captcha.php"alt="Verification pass-phrase" /><hr /><inputtype="Submit"value="Add"name= "Submit" /> 
     Form
 > 
     Body
 > 
     HTML
 >

'). addclass (' pre-numbering '). Hide (); $ (this). addclass (' has-numbering '). Parent (). append ($numbering); for (i = 1; i <= lines; i++) {$numbering. Append ($ ('

'). Text (i)); }; $numbering. FadeIn (1700); }); });

The above describes the PHP drawing function to generate a picture verification code, including the aspects of the content, I hope the PHP tutorial interested in a friend helpful.

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