PHP Verification Code Generation Program Methods

Last Update:2013-12-31 Source: Internet

Author: User

Tags php foreach

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PHP verification code generation is often used to provide a basic security verification function when users register for Logon or publish information. The following section describes some common PHP Verification Code Generation Code and application instances.

Example 1: Use arrays directly. This method is relatively simple.

The Code is as follows:

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<Html>
<Head>
<Meta http-equiv = "Content-Type" content = "text/html; charset = UTF-8">
</Head>
<Body>
<? Php

$ Arr = array (2, 3, 4, 5, 8, 1, 9, 7, "a", "B", "c", "d", "e", "f ", "medium", "country", "South", "North", "big", "small", "more", "less ");
$ B = array_rand ($ arr, 3 );

?>
<Form action = "yz. php" method = "post">
<Input type = "text" name = "code"/>
<Input type = "hidden" name = "yanzhengma" value = "<? Php foreach ($ B as $ key)
{
Echo $ arr [$ key];
}
?> "
/>

<Input type = "submit" name = "submit" value = "do"/>
</Form>
<? Php

Echo "code :";
Foreach ($ B as $ key)
{
Echo $ arr [$ key];
}
?>

</Body>
</Html> (Save the preceding statement as a PHP file)

<? Php
Header ("Content-Type: text/html; charset = UTF-8 ");
Echo $ _ POST ["yanzhengma"];
Echo $ _ POST ["code"];
If ($ _ POST ["yanzhengma"] == _ POST ["code"])
{
Echo "the verification code is correct ";
}
Else
{
Die ("<script> alert ('incorrect Verification Code"); location = "array_rand.php"; </script> ");
}
?>

(Save the preceding statement as yz. php)

Example 2: Use arrays instead of a little more data.

The Code is as follows:

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Function UPCAbarcode ($ code ){
$ Lw = 2; $ hi = 100;
$ Lencode = array ('20140901', '20160901', '20160901', '20160301', '20160301 ',
'123', '123', '123', '123', '123 ');
$ Rencode = array ('20140901', '20160901', '20160901', '20160301', '20160301 ',
'123', '123', '123', '123', '123 ');
$ Ends = '20180101'; $ center = '20180101 ';
/* UPC-A Must be 11 digits, we compute the checksum .*/
If (strlen ($ code )! = 11) {die ("UPC-A Must be 11 digits .");}
/* Compute the EAN-13 Checksum digit */
$ Ncode = '0'. $ code;
$ Even = 0; $ odd = 0;
For ($ x = 0; $ x <12; $ x ++ ){
If ($ x % 2) {$ odd + = $ ncode [$ x];} else {$ even + = $ ncode [$ x];}
}
$ Code. = (10-($ odd * 3 + $ even) % 10) % 10;
/* Create the bar encoding using a binary string */
$ Bars = $ ends;
$ Bars. = $ Lencode [$ code [0];
For ($ x = 1; $ x <6; $ x ++ ){
$ Bars. = $ Lencode [$ code [$ x];
}
$ Bars. = $ center;
For ($ x = 6; $ x <12; $ x ++ ){
$ Bars. = $ Rencode [$ code [$ x];
}
$ Bars. = $ ends;
/* Generate the Barcode Image */
$ Img = ImageCreate ($ lw * 95 + 30, $ hi + 30 );
$ Fg = ImageColorAllocate ($ img, 0, 0, 0 );
$ Bg = ImageColorAllocate ($ img, 255,255,255 );
ImageFilledRectangle ($ img, 0, 0, $ lw * 95 + 30, $ hi + 30, $ bg );
$ Shift = 10;
For ($ x = 0; $ x if ($ x <10) | ($ x >=45 & $ x <50) | ($ x> = 85) {$ sh = 10;} else {$ sh = 0 ;}
If ($ bars [$ x] = '1') {$ color = $ fg;} else {$ color = $ bg ;}
ImageFilledRectangle ($ img, ($ x * $ lw) + 15, 5, ($ x + 1) * $ lw + 14, $ hi + 5 + $ sh, $ color );
}
/* Add the Human Readable Label */
ImageString ($ img, 4,5, $ hi-5, $ code [0], $ fg );
For ($ x = 0; $ x <5; $ x ++ ){
ImageString ($ img, 5, $ lw * (13 + $ x * 6) + 15, $ hi + 5, $ code [$ x + 1], $ fg );
ImageString ($ img, 5, $ lw * (53 + $ x * 6) + 15, $ hi + 5, $ code [$ x + 6], $ fg );
}
ImageString ($ img, 4, $ lw * 95 + 17, $ hi-5, $ code [11], $ fg );
/* Output the Header and Content .*/
Header ("Content-Type: image/png ");
ImagePNG ($ img );
}

UPCAbarcode ('20140901 ');

Example 3: A complete ajax refresh Verification Code instance

Vcode. php

The Code is as follows:

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<? Php
Session_start (); // enable the session Function
Header ("Cache-Control: no-cache, must-revalidate ");

$ Im = imagecreate (60, 30); // you can specify the image width and height.
$ Vcode = getVCode (); // get the characters to be displayed
$ Bg = imagecolorallocate ($ im, 255,255,255); // define the image background
$ Txt = imagecolorallocate ($ im, rand (0,255), rand (0,255), rand (0,255); // defines the color of the characters to be displayed
Imagestring ($ im, 8, 0, 0, $ vcode, $ txt); // write a string to the image
Header (Content-type: image/jpeg); // define Content-type
Imagejpeg ($ im); // display images in JPEG format
$ _ SESSION [vcode] = $ vcode; // write to the SESSION

Function getVCode () {// randomly generates a specified number of strings.
$ Codenum = 4;
$ Checkcode = "";
$ String = ""; // optional string to be displayed, Please define it yourself;
For ($ I = 0; $ I <$ codenum; $ I ){
$ Number = rand (0, 2 );
Switch ($ number) {// can be flexibly defined based on optional strings;
Case 0: $ rand_number = rand (0, 10); break;
Case 1: $ rand_number = rand (11, 36); break;
Case 2: $ rand_number = rand (37,62); break;
}
$ Code = substr ($ string, $ rand_number, 1 );
$ Checkcode = $ checkcode. $ code;
}
Return $ checkcode;
}
?>

Loginform.html

The Code is as follows:

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<! -- Details -->
<Form name = "loginform">
<Table class = "dtable">
<Tr>
<Td width = "100"> User name </td> <input class = "txtbox" name = "loginname" type = text size = "30"/> </ td>
</Tr>
<Tr>
<Td width = "100"> password </td> <input class = "txtbox" name = "loginpwd" type = password size = "30"/> </ td>
</Tr>
<Tr>
<Td width = "100"> Verification Code </td>
<Td> <input class = "txtbox" name = "loginvcode" type = text size = "10"/>

<A href = "javascript: getVCode ();"> change one </a> </td>
</Tr>
</Table>
<Table>
<Tr> <td colspan = "2">
<Input class = "btn" name = "OK" type = "button" value = "login" onclick = "setType ('usr'); usrVCode ();">
<Input class = "btn" name = "reset" type = "reset" value = "Rewrite">
<Input class = "btn" name = "exit" type = "button" value = "exit" onclick = "Hide ();">
</Td> </tr>
</Table>
<Table>
<Tr> <td colspan = "2">
Not registered yet? <A href = "javascript: setType ('usr'); Show ('0', 'addform');"> Register now </a>
Forgot password? <A href = "javascript: setType ('usr'); Show ('0', 'pwdform');"> retrieve password </a>
</Td> </tr>
</Table>
</Form>

Vcode. js

The Code is as follows:

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// This function is used to obtain the verification code.

Function getVCode (){
Var vcode = document. getElementById ('vcode ');
Vcode. src = 'vcode. php? Nocache = '+ new Date (). getTime ();
}

// This function is used to verify the verification code
Function usrVCode (){
If (! CheckLogin () return false;
Var loginvcode = document. loginform. loginvcode. value;
Var xmlhttp1 = createAjax ();
Var data = '& loginvcode =' + loginvcode;
If (xmlhttp1 ){
Var state = document. getElementById ('state ');
Xmlhttp1.open ('get ',? Do = vcodedo '+ data, true );
Xmlhttp1.send (null );
Xmlhttp1.onreadystatechange = function (){
If (xmlhttp1.readyState = 4 & xmlhttp1.status = 200 ){
SetTimeout ("state. style. display = 'none';", 1000 );
Var myres = xmlhttp1.responseText;
Var result = (myres = 1 )? "Congratulations, the verification code is entered correctly! ":" Sorry, incorrect verification code! ";
If (myres = 0) alert (result );
If (myres = 1) usrLogin ();
}
Else {
State. style. display = "";
State. style. left = (document. body. offsetWidth-350)/2;
State. style. top = (document. body. offsetHeight-235)/2 + document. body. scrollTop;
}
}
}
}

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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