Verification code + background login + Click to display the verification code

Verification code for the mxnenews system (including five files)
Function. Java
Verifycode. Java
Verifycode. jsp
Usage page, processing page)
1. Page for verification code

 

Verification Code:

<Input name = "verifycode" type = "text" class = "Chinese" id = "verifycode" style = "font-size: 12px" size = "6"

 

Maxlength = "6">

<! -- Error message -->

<% = (String) Session. getattribute ("error") = NULL )? "": (String) Session. getattribute ("error") %>

2. Processing page

String scode = function. checkreplace (request. getparameter ("verifycode "));

If (! Scode. Equals (session. getattribute ("verifycode ")))

{

Session. setattribute ("error", "<li> Verification code error ");

Response. sendredirect ("index. jsp"); // return to the logon page

Return;

}

3. The source code is provided below for learning and researching verifycode. jsp.

<Meta http-equiv = "Content-Type" content = "text/html; charset = gb2312">

<% @ Page contenttype = "text/html; charset = gb2312" Language = "Java" Import = "Java. AWT. *, java. AWT. image. *" %>

<% @ Page import = "Java. util. *, javax. ImageIO. *, java. Io. *" %>

<% @ Page import = "dreamtime. dreamnews. verifycode" %>

 

<%! String sverifycode; // verification code string %>

 

<% // Set that the page is not cached

Response. setheader ("Pragma", "No-Cache ");

Response. setheader ("cache-control", "No-Cache ");

Response. setdateheader ("expires", 0 );

Response. Reset ();

 

Try {

// Save the authentication code to the session

// Call runverifycode (int I) and change I to the number of digits of the Verification Code

Verifycode Vc = new verifycode ();

Session. setattribute ("verifycode", VC. runverifycode (4 ));

// Session. setmaxinactiveinterval (60 );

// Output the image to the page

Sverifycode = (string) Session. getattribute ("verifycode ");

Outputstream outs = response. getoutputstream ();

ImageIO. Write (VC. createimage (sverifycode), "Jpeg", outs );

} Catch (exception e ){

Return;

}

%>

 

4. verifycode. Java

/*************************************** ************

*

* Source File Name: verifycode. Java

* Success: Dream news system-Verification Code

* Author: dreamtime

* Email: fanwsp@126.com

* QQ: 122142023

* Copyright (c) 2005-2006 by dreamtime

*

**************************************** ************

*/

 

 

Package dreamtime. dreamnews; // package where the specified class is located

Import java. AWT. *; // import class

Import java. AWT. image .*;

Import java. util .*;

Import javax. ImageIO .*;

 

// Define a class

 

Public class verifycode {

Static random r = new random ();

Static string ssource = "abcdefghijklmnopqrstuvwxyz" + "abcdefghijklmnopqrstuvwxyz" +

 

"0123456789 ";

Static char [] src = ssource. tochararray ();

 

 

// Generate a random string

 

Private Static string randstring (INT length ){

Char [] Buf = new char [length];

Int RND;

For (INT I = 0; I <length; I ++ ){

RND = math. Abs (R. nextint () % SRC. length;

Buf [I] = SRC [RND];

}

Return new string (BUF );

}

 

// Call this method to generate a random string,

// Parameter I: String Length

Public String runverifycode (int I ){

String verifycode = randstring (I );

Return verifycode;

}

 

 

// Obtain the random color in a given range

Public color getrandcolor (int fc, int BC)

{

Random random = new random ();

If (FC> 255) fc = 255;

If (BC> 255) BC = 255;

Int r = FC + random. nextint (BC-Fc );

Int G = FC + random. nextint (BC-Fc );

Int B = FC + random. nextint (BC-Fc );

Return new color (R, G, B );

}

// Call this method to generate an image for the obtained Verification Code

// Scode: Pass the verification code W: Image Width H: Image Height

Public bufferedimage createimage (string scode)

{

Try {

// Character Font

Font codefont = new font ("Arial black", Font. Plain, 16 );

Int ilength = scode. Length (); // obtain the verification code length.

Int width = 22 * ilength, Height = 20; // image width and height

Int charwidth = (INT) (width-24)/ilength; // The width of the character from the left

Int charheight = 16; // character distance

 

Edge height

// Create an image in memory

Bufferedimage image = new bufferedimage (width, height, bufferedimage. type_int_rgb );

// Obtain the image Context

Graphics G = image. getgraphics ();

// Generate a random class

Random random = new random ();

// Set the background color

G. setcolor (getrandcolor (200,240 ));

G. fillrect (0, 0, width, height );

// Set the font

G. setfont (codefont );

// Draw a border with random colors

G. setcolor (getrandcolor (10, 50 ));

G. drawrect (0, 0, width-1, height-1 );

// Generates 155 random interference lines, making the authentication code in the image hard to be detected by other programs.

G. setcolor (getrandcolor (160,200 ));

For (INT I = 0; I <155; I ++)

{

Int x = random. nextint (width );

Int y = random. nextint (height );

Int XL = random. nextint (12 );

Int yl = random. nextint (12 );

G. drawline (X, Y, x + XL, Y + yl );

}

 

For (INT I = 0; I <ilength; I ++)

{

String Rand = scode. substring (I, I + 1 );

// Display the authentication code to the image

G. setcolor (new color (20 + random. nextint (60), 20 + random. nextint

 

(120), 20 + random. nextint (180 )));

G. drawstring (RAND, charwidth * I + 14, charheight );

}

// The image takes effect

G. Dispose ();

Return image;

} Catch (exception e ){

// E. printstacktrace ();

// System. Out. println (E. getmessage ());

}

Return NULL;

}

 

// Test

Public static void main (string [] ARGs ){

// Verifycode Vc = new verifycode ();

// String S1 = VC. runverifycode (4 );

// Fun. dreamnewstitle; system. Out. println (S1 );

// Image im = VC. createimage (S1 );

// Graphics G = Im. getgraphics ();

// G. drawimage (IM, 20, 20, this );

// G. drawstring (S1, 20, 20 );

}

}

5. function. Java
Import java. SQL .*;
Import java. util. calendar;
Public class function {
/*************************************** ************************************
* Function name: checkreplace used for conversion SQL special string parameter: S: string type, character return value to be converted: converted string
* Use: String S2 = checkreplace (S1 );
**************************************** **********************************/
 
Public static string checkreplace (string s ){
Try {
If (S = NULL | S. Equals (""))
Return "";
Else {
Stringbuffer = new stringbuffer ();
For (INT I = 0; I <S. Length (); I ++ ){
Char c = S. charat (I );
Switch (c ){

Case 34: // & apos; "& apos;
Stringbuffer. append ("& quot ;");
Break;

Case 39: // & apos;/& apos;
Stringbuffer. append ("& #039 ;");
Break;

Case 124: // & apos; | & apos;
Stringbuffer. append ("");
Break;

Case & apos ;:
Stringbuffer. append ("& amp ;");
Break;

Case & apos; <& apos ;:
Stringbuffer. append ("& lt ;");
Break;

Case & apos;> & apos ;:
Stringbuffer. append ("& gt ;");
Break;

Default:
Stringbuffer. append (C );
Break;
}
}
Return stringbuffer. tostring (). Trim (); // return the converted string
}
} Catch (exception e ){
Return "";
}
}
}

 

Appendix:

Background Management instructions:
Address: For admin/index. jsp, you must enter the file name index. jsp. Otherwise, you cannot log on.
Because string page1 = (string) request. getheader ("Referer"); // obtain the page Address Source
String page2 = request. getrequesturl (). tostring (); // obtain the current page address.
If (page2.equals (page1) // you cannot directly log on via http: // localhost/admin. You must use http:/index. jsp to log on.
 
Username: Admin
Password: Admin (74d839d98630e280df752e8939454a6b)
Appendix 2: Click to bring up the verification code, which is used for the message. When the message box is activated, the verification code is issued, saving the network speed.
<Div id = "verify" style = "display: none;">
</Div>
<Script language = "JavaScript">
Function creatediv ()
{
Document. getelementbyid ("verify"). style. Display = "Block ";
Document. getelementbyid ("verify"). innerhtml = " ";
}
</SCRIPT>
<Input name = "verifycode" type = "text" class = "Chinese" id = "verifycode" style = "font-size: 12px "size =" 6 "maxlength =" 6"
Onclick = "creatediv ();";
Onfocus = "creatediv ();"
Onblur = "document. getelementbyid ('verify '). style. Display = 'none ';"
/>