Driving novices on the road PHP novices on the road (6)

Building a simple interactive website (2)
5.5 Counter
　Let us add a counter to the homepage. This example has been told many times, but it is still useful to demonstrate how to read and write files and create your own functions. counter.inc contains the following code:

/*
|| A simple counter
*/
function get_hitcount($counter_file)
{
/* Return the counter to zero
This way, if the counter has not been used, the initial The value will be 1
Of course you can also set the initial value to 20000 to fool people
*/
$count=0;
// If the file to store the counter already exists, read its contents
if ( file_exists($counter_file ) )
{
$fp=fopen($counter_file,"r");
// We only took the top 20, I hope your site will not be too popular
$count=0+fgets($fp,20 );
// Since the function fgets() returns a string, we can automatically convert it to an integer by adding 0
fclose($fp);
// The file operation is completed
}
// Increase the count value once
$count++;
//Write the new count value to the file
$fp=fopen($counter_file,"w");
fputs($fp,$count);
fclose($fp);
# Return count value
return ($count);
}
?>
Then we change the front.php3 file to display this counter:

include("include/counter.inc");
// I put the count value Place it in the file counter.txt, read and output
printf ("

%06d
n",
get_hitcount("counter.txt" ));
include("include/footer.inc");
?>
Check out our new front.php3
5.6 Feedback Form
　Let us add another feedback form for your visitors to fill out and e-mail for you. For example, we use a very simple method to implement it. We only need two pages: one to provide the viewer with an input form; the other to obtain the form data, process it, and mail it to you.
　Getting form data in PHP is very simple. When a form is sent, each element contained in the form is assigned a corresponding value, and can be used like a reference to a general variable.

> ;
　In process_form.php3, the variable $mytext is assigned the entered value - very simple! Similarly, you can get variable values ​​from form elements such as list boxes, check boxes, radio boxes, buttons, etc. The only thing you have to do is give each element in the form a name so that you can reference it later.
　According to this method, we can generate a simple form containing three elements: name, e-mail address and message. When the visitor sends the form, the PHP page (sendfdbk.php3) that processes the form reads the data, checks whether the name is empty, and finally emails the data to you.
Form: form.php3

include("include/common.inc");
$title = "Feedback";
include("include/header.inc");
?>

<br>Your feedback on my home page. <br>



FORM>
;
$title = "Feedback";
include("include/header.inc");
if ( $name == "" )
{
// Now I hate anonymous comments!
echo "Duh ? How come you are anonymous?";
}
elseif ($name == "Your name")
{
// This viewer really doesn’t want to be named!
echo "Hello ? Your name is supposed to be replaced with
your actual name!";
}
else
{
// Output a polite thank you
echo "
Hello, $name.


Thank you for your feedback.
// Finally send the email
mail($MyEmail, "Feedback.","
Name : $name
E-mail : $email
Comment : $comment
");
}
include("include/footer.inc ");
?>
　 Note: If the program does not work properly during your test, please check whether your PHP configuration file (php3.ini for PHP3, php.in for PHP4) is set properly. Because this program requires the following settings in your PHP configuration file:
First, use NotePad to open your php3.ini or php.ini file and check whether [mail function] has been set up. The default situation is as follows:
SMTP = localhost
sendmail_from = me@localhost.com
Set SMTP server for SMTP, preferably your local SMTP server. I will use the SMTP server of 21cn as an example. Then, fill in your E-MAIL in sendmail_from The address, for example, can be changed to this:
SMTP = smtp.21cn.com
sendmail_from = pert@21cn.com
Don’t forget to restart the Apache, IIS or PWS service after modification.
5.7 Simple on-site search engine
　 PHP can be called external program. In a Unix environment we can use the program grep to implement a simple search engine. We can make it a little more complicated: use a page to output a form for users to enter search strings and output query results.

include("include/common.inc");
$title = "Search";
include("include/header.inc");
?>

" METHOD="POST">
SIZE="20" MAXLENGTH="30">

if ( ! empty($searchstr) )
{
// empty() is used to check whether the query string is empty
// If it is not empty, call grep query
echo "

---

n";
// call grep queries all files in case-insensitive mode
$cmdstr = "grep -i $searchstr *";
$fp = popen( $cmdstr, "r" ); // Execute the command and output the pipe
$myresult = array(); // Store query results
while( $buffer = fgetss ($fp, 4096))
{
{
// grep returns this format: File name: the number of lines in the matching string
// So we use the function split () Separate and process data
list($fname, $fline) = split(":",$buffer, 2);
// We only output the result of the first match
if ( !defined($myresult[$fname ]))
$myresult[$fname] = $fline;
}
// Now we store the results in the array, we can process and output them
if ( count($myresult) )
{
echo "< ;OL>n";
while(list($fname,$fline) = each($myresult))
echo "

$fname : $fline

n";
echo "n";
}
else
{
// If there are no query results
echo "Sorry. Search on $searchstr> ;
returned no results.
n";
}
pclose($fp);
}
?>

include("include/footer.inc");
?>
Comments :
PHP_SELF is a built-in variable in PHP. Contains the current file name.
fgets() reads the file line by line, with a maximum length of 4096 (specified) characters.
fgetss() is similar to fgets(), except that it parses the output HTML tags.
split() has a parameter of 2, because we only need to split the output into two parts. Also need to omit ":".
each() is an array operation function, used to traverse the entire array more conveniently.
popen(), pclose() have very similar functions to fopen(), fclose(), except that pipeline processing is added.
Please note that the above code is not a good way to implement a search engine. This is just an example to help us learn PHP better. Ideally you should build a database of keywords and then search them.​

The above has introduced the PHP novice on the road (6), including the content of the novice driving on the road. I hope it will be helpful to friends who are interested in PHP tutorials.

🎜