PHP mysqli_use_result()用法及代码示例

定义和用法

这个mysqli_use_result()函数开始从先前执行的查询中检索结果集

用法

mysqli_use_result($con)

参数

Sr.No	参数及说明
1	con(Mandatory) 这是一个表示与 MySQL 服务器的连接的对象。

返回值

mysqli_use_result() 函数在出错时返回一个结果对象和布尔值 false。

PHP版本

这个函数最初是在 PHP 版本 5 中引入的，适用于所有后续版本。

示例

以下示例演示了 mysqli_use_result() 函数的用法(程序风格) -

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "test");

   //Executing the multi query
   $query = "SELECT * FROM players;SELECT * FROM emp;SELECT * FROM tutorials";
   $res = mysqli_multi_query($con, $query);

   $count = 0;

   if ($res) {
      do {
         $count = $count+1;
	      mysqli_use_result($con);
     } while (mysqli_next_result($con));
   }
   print("Number of result sets:".$count);
   mysqli_close($con);
?>

这将产生以下结果 -

Number of result sets:3

示例

在面向对象的风格中，这个函数的语法是 $con->use_result();以下是面向对象样式 $minus 中此函数的示例；

<?php
   $con = new mysqli("localhost", "root", "password", "test");

   //Multi query
   $res = $con->multi_query("SELECT * FROM players;SELECT * FROM emp;SELECT * FROM tutorials");

   $count = 0;
   if ($res) {
      do {
         $count = $count+1;
         $con-> use_result();
   } while ($con->next_result());
}
print("Number of result sets:".$count);

//Closing the connection
$res = $con -> close();
?>

这将产生以下结果 -

Number of result sets:3

示例

以下示例检索 muti-query 的所有结果集的记录 -

//Creating a connection
$con = mysqli_connect("localhost", "root", "password", "test");

//Executing the multi query
$query = "SELECT * FROM players;SELECT * FROM emp";

$res = mysqli_multi_query($con, $query);

if ($res) {
   do {
      if ($result = mysqli_use_result($con)) {
         while ($row = mysqli_fetch_row($result)) {
            print("Name:".$row[0]."\n");
            print("Age:".$row[1]."\n");
         }
         mysqli_free_result($result);
      }
      if (mysqli_more_results($con)) {
         print("\n");
      }
   } while (mysqli_use_result($con));
}
mysqli_close($con);

这将产生以下结果 -

Name:Dhavan
Age:33
Name:Rohit
Age:28
Name:Kohli
Age:25

Name:Raju
Age:25
Name:Rahman
Age:30
Name:Ramani
Age:22