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mysqli_stmt::$param_count

mysqli_stmt_param_count

(PHP 5)

mysqli_stmt::$param_count -- mysqli_stmt_param_countReturns the number of parameter for the given statement

说明

面向对象风格

int $mysqli_stmt->param_count ;

过程化风格

int mysqli_stmt_param_count ( mysqli_stmt $stmt )

Returns the number of parameter markers present in the prepared statement.

参数

stmt

仅以过程化样式:由 mysqli_stmt_init() 返回的 statement 标识。

返回值

Returns an integer representing the number of parameters.

范例

Example #1 面向对象风格

<?php
$mysqli 
= new  mysqli ( "localhost" "my_user" "my_password" "world" );


if ( mysqli_connect_errno ()) {
    
printf ( "Connect failed: %s\n" mysqli_connect_error ());
    exit();
}

if (
$stmt  $mysqli -> prepare ( "SELECT Name FROM Country WHERE Name=? OR Code=?" )) {

    
$marker  $stmt -> param_count ;
    
printf ( "Statement has %d markers.\n" $marker );

    

    
$stmt -> close ();
}


$mysqli -> close ();
?>

Example #2 过程化风格

<?php
$link 
mysqli_connect ( "localhost" "my_user" "my_password" "world" );


if ( mysqli_connect_errno ()) {
    
printf ( "Connect failed: %s\n" mysqli_connect_error ());
    exit();
}

if (
$stmt  mysqli_prepare ( $link "SELECT Name FROM Country WHERE Name=? OR Code=?" )) {

    
$marker  mysqli_stmt_param_count ( $stmt );
    
printf ( "Statement has %d markers.\n" $marker );

    

    
mysqli_stmt_close ( $stmt );
}


mysqli_close ( $link );
?>

以上例程会输出:

Statement has 2 markers.

参见

  • mysqli_prepare() - Prepare an SQL statement for execution

用户评论:

[#1] Senthryl [2009-03-10 11:47:26]

This parameter (and presumably any other parameter in mysqli_stmt) will raise an error with the message "Property access is not allowed yet" if the statement was not prepared properly, or not prepared at all.

To prevent this, always ensure that the return value of the "prepare" statement is true before accessing these properties.

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