Chat room design based on PHP+MySQL_PHP tutorial

In website development, the author used PHP4.0+MySQL3.23.38 to build a variety of applications. Next, take a simple chat room design as an example to introduce the application of PHP+MySQL in web development.

1. Overall design

　1． 1 Concept and planning:

The basic principle of the chat room is to store the speech data sent by each user connected to the same web page, and then transmit all the speech data to each user. In other words, the function of a chat room is realized by using a database to collect everyone's speeches and transmitting the data in the database to everyone.

　1.2 Table design

First use MySQL to create a table chat to store user comments:

Copy code The code is as follows:

mysql> CREATE TABLE chat
-> (chtime DATATIME,
-> nick CHAR(10) NOT NULL,
->words CHAR(150));

Only three fields are set in the table, chtime is the time of speaking, nick is the nickname of the speaker, words is the content of the speech, and the speech can be up to 150 characters

　1.3 Web Design

The simplest chat room usually requires two page frames: one page frame is the form for users to enter comments, and the other is used to display everyone's comments. So the code segment usually requires at least the following segments:

Create the structure of the page frame (main.php)

Display the program segment where everyone speaks (cdisplay.php)

Transmit the program segment (speak.php) where the user speaks

User login to enter the chat room program segment (login.php)

　2. Code design

After the above planning is completed, you can start code design. Using PHP can realize the above functions very simply.

2.1 User login login.php, this code is a complete HTML web page

Copy code The code is as follows:

Please enter your nickname

After the user submits his nickname, he enters the chat room, and the following processing is handled by main.php.

　2.2 Main code segment of page frame main.php:

Copy code The code is as follows:

setcookie("nick",$nick) //Use Cookie records user nickname, which is a commonly used method of passing variables
?>


< frameset rows="80%,*">

　2.3 Display speech cdisplay.php

The task of this code segment is to extract the data from the chat table and display it in the page frame. Each time it is refreshed, the 15 most recent statements in the database are fetched. At the same time, in order to prevent the database from growing indefinitely, it is necessary to design the function of deleting old data. The code is as follows

Copy code The code is as follows:

$link_ID=mysql_connect("main","root");
/ /Link Mysql server server name is main, administrator name is root
mysql_select_db("abc"); //Select database
$str="select * from chat ORDER BY chtime;"; //Query string
$result=mysql_query($str, $link_ID); //Send query
$rows=mysql_num_rows($result); //Get the number of records of query results
//Get the last 15 statements , and display
@mysql_data_seek($resut,$rows-15); //Move the record pointer to the first 15 records
if ($rows<15) $l=$rows; else $l=15; //The total number of records is less than 15, then the maximum number of records is
for ($i=1;$i<=$l;$i++) {
list($chtime,$nick,$words)=mysql_fetch_row ($result);
echo $chtime; echo " ";echo $nick; echo":" ; echo $words; echo "
";
}
//Clear obsolescence in the library Data
@mysql_data_seek($result,$rows-20); //Move the record pointer to the first 20 records
list($limtime)=mysql_fetch_row($result);
$str="DELETE FROM chat WHERE chtime<'$limtime' ;" ;
$result=mysql_query($str,$link_ID); //Send the query string, leaving only the first 20 records in the library
mysql_close($link_ID) ;
?>

　2.4 Send speech to database speak.php

Copy code The code is as follows:

If ($words)
{ $link_ID=mysql_connect("main","root ");
mysql_select_db("abc"); //The database name is abc
$time=date(y).date(m).date(d).date(h).date(i). (date(s); //Get the current time
$str="INSERT INTO chat(chtime,nick,words) values ​​
('$time','$nick','$words');" ;
mysql_query($str,$link_ID); //Send a statement to the database
mysql_close($link_ID);
}
?>
//Enter the form for making a statement


< input type="submit" value="Speak">

After completing the above work , a simple chat room is completed. Of course, the designer can make some personalized designs according to personal preferences, such as adding a page frame to display the list of current chat room members, adding speaking emoticons, obtaining the speaker's IP, and further beautifying the page. Wait.

http://www.bkjia.com/PHPjc/314593.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/314593.htmlTechArticleIn website development, the author used PHP4.0+MySQL3.23.38 to build a variety of applications. Next, take a simple chat room design as an example to introduce the application of PHP+MySQL in web development. 1. Overall...