PHP mysqli_stmt_prepare()用法及代码示例

定义和用法

这个mysqli_stmt_prepare()函数准备执行的 SQL 语句，您可以在此查询中使用参数标记 ("?")，为其指定值，并稍后执行。

用法

mysqli_stmt_prepare($stmt, $str);

参数

Sr.No	参数及说明
1	stmt(Mandatory) 这是一个表示语句的对象(由 mysqli_stmt_init() 函数返回)。
2	str(Mandatory) 这是指定所需查询的字符串值。

返回值

此函数返回一个布尔值，它在成功时为真，在失败时为假。

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_stmt_prepare() 函数的用法(程序风格) -

<?php
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   $query = "CREATE TABLE Test(Name VARCHAR(255), AGE INT)"; 
   mysqli_query($con, $query);
   print("Table Created.....\n");

   //Initializing the statement
   $stmt = mysqli_stmt_init($con);

   mysqli_stmt_prepare($stmt, "INSERT INTO Test values(?, ?)");
   mysqli_stmt_bind_param($stmt, "si", $Name, $Age);
   $Name = 'Raju';
   $Age = 25;
   print("Record Inserted.....");

   //Executing the statement
   mysqli_stmt_execute($stmt);

   //Closing the statement
   mysqli_stmt_close($stmt);

   //Closing the connection
   mysqli_close($con);
?>

这将产生以下结果 -

Table Created.....
Record Inserted.....

示例

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

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

   $query = "CREATE TABLE Test(Name VARCHAR(255), AGE INT)"; 
   $con->query($query);
   print("Table Created.....\n");

   //Initializing the statement
   $stmt = $con->stmt_init();

   $stmt->prepare("INSERT INTO Test values(?, ?)");
   $stmt->bind_param("si", $Name, $Age);
   $Name = 'Raju';
   $Age = 25;
   print("Record Inserted.....");

   //Executing the statement
   $stmt->execute();

   //Closing the statement
   $stmt->close();

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

这将产生以下结果 -

Table Created.....
Record Inserted.....

示例

让我们看看这个函数的另一个例子是使用 SELECT 查询(面向对象的风格) -

<?php
   //Creating a connection
   $con = new mysqli("localhost", "root", "password", "mydb");

   $con -> query("CREATE TABLE myplayers(ID INT, First_Name VARCHAR(255), Last_Name VARCHAR(255), Place_Of_Birth VARCHAR(255), Country VARCHAR(255))");
   print("Table Created.....\n");
   $con -> query("INSERT INTO myplayers values(1, 'Sikhar', 'Dhawan', 'Delhi', 'India')");
   $con -> query("INSERT INTO myplayers values(2, 'Jonathan', 'Trott', 'CapeTown', 'SouthAfrica')");
   $con -> query("INSERT INTO myplayers values(3, 'Kumara', 'Sangakkara', 'Matale', 'Srilanka')");
   $con -> query("INSERT INTO myplayers values(4, 'Virat', 'Kohli', 'Delhi', 'India')");
   print("Records Inserted.....\n");

   //Initiating the statement object
   $stmt = $con->stmt_init();

   $stmt -> prepare("SELECT * FROM myplayers WHERE country=?");
   $stmt -> bind_param("s", $country);
   $country = "India";

   //Executing the statement
   $stmt->execute();

   //Closing the statement
   $stmt->close();

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

这将产生以下结果 -

Table Created.....
Records Inserted.....