Home > Article > Backend Development > Comprehensive list of commonly used PHP codes (essential for beginners)_PHP tutorial
1. Connect the MYSQL database code
$connec=mysql_connect("localhost","root","root") or die("Cannot connect to the database server: ".mysql_error());
mysql_select_db("liuyanben",$connec) or die ("Cannot select database: ".mysql_error());
mysql_query("set names 'gbk'");
?>
2. Read the database and implement loop output
$sql="select * from liuyan order by ly_id desc";
$conn=mysql_query($sql,$connec) ;
while($rs=mysql_fetch_array($conn)){
?>
The content of the loop...
}
?>
3. How to implement paging, including two functions and two calls
1) Two functions
//Paging function
function genpage (&$sql,$page_size=2)
{
global $prepage,$nextpage,$pages,$sums; //out param
$page = $_GET["page"];
$eachpage = $page_size;
$pagesql = strstr($sql," from ");
$pagesql = "select count(*) as ids ".$pagesql;
$conn = mysql_query( $pagesql) or die(mysql_error());
if($rs = mysql_fetch_array($conn)) $sums = $rs[0];
$pages = ceil(($sums-0.5)/$ eachpage)-1;
$pages = $pages>=0?$pages:0;
$prepage = ($page>0)?$page-1:0;
$nextpage = ($ page<$pages)?$page+1:$pages;
$startpos = $page*$eachpage;
$sql .=" limit $startpos,$eachpage ";
}
/ / Show paging
function showpage()
{
global $page,$pages,$prepage,$nextpage,$queryString; //param from genpage function
$shownum =10/2;
$startpage = ($page>=$shownum)?$page-$shownum:0;
$endpage = ($page+$shownum<=$pages)?$page+$shownum:$pages;
echo "Total".($pages+1)."Pages: ";
if($page>0)echo "Homepage a>";
if($startpage>0)
echo " ... ?";
for($i=$startpage;$i<=$endpage;$i++)
{
if($i==$ page) echo " [".($i+1)."] ";
else echo " ". ($i+1)." ";
}
if($endpage<$pages)
echo "? ... ";
if($page<$pages)
echo "Last page";
}
//Show pagination with categories
function showpage1()
{
$fenlei =$_GET["fenleiid"];
global $page,$pages,$prepage,$nextpage,$queryString; //param from genpage function
$shownum =10/2;
$startpage = ($page>=$shownum)?$page-$shownum:0;
$endpage = ($page+$shownum<=$pages)?$page+$shownum:$pages;
echo " Total ".($pages+1)." pages: ";
if($page>0)echo "Homepage ";
if($startpage>0)
echo " ... ?";
for($i=$startpage;$i<=$endpage;$i++)
{
if($i== $page) echo " [".($i+1)."] ";
else echo " ".($i+1)." ";
}
if($endpage<$pages)
echo "? ... ";
if($page<$pages)
echo "Last page}
?>
2) Two Call
First
$sql="select * from liuyan order by ly_id desc";
genpage($sql); //Just add this line to the normal code It’s OK.
$conn=mysql_query($sql,$connec);
while($rs=mysql_fetch_array($conn)){
?>
Second
}
?>
showpage(); //Show page
?>
mysql_close();
?>
4. The server side includes
5. How to write a record into the database, and then Prompt and jump to the page
$ly_title=$_POST["ly_title"];
$ly_content=$_POST["ly_content"];
$ly_time=$_POST[" ly_time"];
$ly_author=$_POST["ly_author"];
$ly_email=$_POST["ly_email"];
$sql="insert into liuyan(ly_title,ly_content,ly_time,ly_author ,ly_email) values('".$ly_title."','".$ly_content."','".$ly_time."','".$ly_author."','".$ly_email."') ";
mysql_query($sql,$connec);
echo("");
?>
6. A dialog box pops up and a page jump occurs
echo("");
?>
7. Information viewing Page (conditionally read database)
1) Conditionally read database
$sql="select * from liuyan where ly_id=$_GET[id]";
$ conn=mysql_query($sql,$connec);
$rs=mysql_fetch_array($conn);
?>
2) Output a field
=$rs[ly_title ]?>
3) Close the database
mysql_close();
?>
8. Update a record in the database and Make prompt jump
$ly_title=$_POST["ly_title"];
$ly_content=$_POST["ly_content"];
$ly_time=$_POST["ly_time "];
$ly_author=$_POST["ly_author"];
$ly_email=$_POST["ly_email"];
$sql="update liuyan set ly_title='$ly_title',ly_content= '$ly_content',ly_time='$ly_time',ly_author='$ly_author',ly_email='$ly_email' where ly_id=$_GET[id]";
mysql_query($sql,$connec);
echo("");
?>
9. How to delete a record in the database
< ?php
$sql="delete from liuyan where ly_id=$_GET[id]";
mysql_query($sql,$connec);
echo("");
?>
10. How to log in as a member Verification
session_start();
$username=$_POST["username"];
$password=$_POST["password"];
$sql=" select * from admin where username='".$username."' && password='".$password."'";
$result=mysql_query($sql,$connec);
if($row =mysql_fetch_array($result)){
session_register("admin");
$admin=$username;
echo("");}
else
{
echo("}
mysql_close();
?>
11. How to check SESSION (production of background check page)
session_start();
if(!isset($_SESSION[" admin"])){
header("location:login.php");
exit;
}
?>
12. Verify that the username and password are filled in (javascript)
13. How to call the editor in PHP
1) Place the editor folder in the background management folder.
2) Use the following statements to perform the import operation.
Note: The name of the eWebEditorPHP38 editor folder.
The content in id=content is the name of the hidden field above
14. Loop output (can achieve column splitting)
1) First insert a row and a column table
$i=1;
?>
Other tables and outputs to be looped |