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A "universal" query paging class that can query all tables_PHP tutorial
- WBOYOriginal
- 2016-07-21 16:09:10957browse
A "universal" query pagination class that can query all tables
Recently, I had a whim, hoping to write a query paging class that can target all tables. Because in actual development, I am afraid that querying and paging the result set is the most used code, and the structure of the table is diverse. I want to improve the reuse rate and maintainability of the code as much as possible.
The following is what I wrote. Please give me your guidance and test it to see if I can make better improvements and get more support.
Currently, it only supports a single table and does not support joint queries. But we may consider how to support it in the future.
Code:
/***************************************************** ************
This class is mainly used to solve simple data queries for many tables, and is still being improved. I hope netizens can provide more comments and suggestions.
My goal is to develop a class that can be applied to queries on almost all mysql tables and paginate the result set.
Can automatically identify the field values to be displayed in the query.
I would like to express my special thanks to the friends of chinaunix, especially the netizens of the PHP version for their long-term help.
A special mention goes to NightKids, who has always given me selfless help, even his source code.
This class can be freely referenced, used, and modified by anyone. But please keep this text.
All losses caused by using this class have nothing to do with the author tonera.
I am still considering that for some complex joint queries, we can derive a class and reconstruct the sql implementation.
This class does not consider more display styles, you can construct it yourself.
**************************************************** ********************/
class browser{
var $c_table; //Table name to be queried
var $c_rows; //Number of rows to be displayed
var $c_lation; //Query conditions
var $c_order; //Sort conditions
var $c_result; //Query data connection handle
var $c_query; //Finally constructed query
var $c_found; //Result set
var $c_error; //Error collector
var $c_offset; //Offset displayed in paging
var $total; //The total number of result sets
//Connect to the database
function connect(){
include '../connect.inc.php';
if ( $connection==false){
$this->c_error.="Not connected to the database.
";
exit;
}
$this->c_result=$ connection;
}
//Constructor, initialize variables
function browser($tablename,$row,$sql,$lation,$orderby){
$this->c_table =$tablename;
$this->c_rows=$row;
if(empty($this->c_offset)){
$this->c_offset=0;
}
if (empty($tablename) or empty($row) or empty($sql)){
$this->c_error="There is no query table or no number of rows to be displayed or no query statement< ;br>";
}
$this->c_query=$sql;
if (!empty($lation)){
$this->c_query.=" ".$ lation;
}
if (!empty($orderby)){
$this->c_query.=" ".$orderby;
}
}
//Calculate the total number of pages
function TatolPage(){
$sult=mysql_query("select count(*) as 'total_rows' from $this->c_table",$this->c_result);
if ($sult==false) {
$this->c_error.="The query failed to calculate the total number of result sets, please check.
";
exit;
}
$tempvar=mysql_fetch_array($sult);
$this->total=$tempvar[0];
}
//Get the result set from the query and store it in the array c_found[][]
function GetFound(){
$sult=mysql_query($this->c_query,$this->c_result) or die(mysql_error());
while ($found=mysql_fetch_array($sult)){
$this->c_found[]=$found;
}
}
//Query the data and store the results in pages into a variable
function ShowTable(){
$this->connect();
$this->TatolPage();
if (empty($_GET[offset])){
$_GET[offset]=0;
}
$this->c_query.=" limit ".$_GET[ offset].", ".$this->c_rows;
$sult=mysql_query($this->c_query,$this->c_result) or die(mysql_error());
//Parse the query and get the field value to be displayed
$tempvar=explode(" ",$this->c_query);
$fields=explode(",",$tempvar[1]); //Field value (array)
//Display data to a table
$echo_content.="
| "; $echo_content.="".$found[1]." | "; ".$found[$i]." | ";||||||||
| Previous page&"; }else{ $echo_content.=" | |||||||||
| Previous page&"; Page number for($i=1;$i<=$total_page;$i++){ if ($_GET[offset]/$this->c_rows==($i-1)){ } !=0 and ($_GET[offset]+$this->c_rows)<=$this->total){ $echo_content.="&Next page | |||||||||
return $echo_content;
}
}
/*Example
//browser("table name", number displayed on each page, "sql", "query conditions", "sorting conditions");
$gggg=new browser ("news",5,"select auto_id,news_title from news","","order by newstime desc");
$temp=$gggg->ShowTable();
echo $ temp;
//$gggg->GetFound() stores the query result set in a two-dimensional array, which is not used in this example.
*/
?>