mysqli_result::fetch_fields

定義和用法

fetch_fields() / mysqli_fetch_fields()函數返回一個對像數組，這些對象表示結果集中的字段。

實例

例子1 - 面向對像風格

返回一個對像數組，這些對象表示結果集中的字段，然後打印每個字段的名稱、表和最大長度：

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

if ( $mysqli -> connect_errno ) {
  echo "Failed to connect to MySQL: " . $mysqli -> connect_error ;
  exit ( ) ;
}

$sql = "SELECT Lastname, Age FROM Persons ORDER BY Lastname" ;

if ( $result = $mysqli -> query ( $sql ) ) {

  // 獲取所有字段的字段信息
  $fieldinfo = $result -> fetch_fields ( ) ;

  foreach ( $fieldinfo as $val ) {
    printf ( "Name: %s\n" , $val -> name ) ;
    printf ( "Table: %s\n" , $val -> table ) ;
    printf ( "Max. Len: %d\n" , $val -> max_length ) ;
  }
  $result -> free_result ( ) ;
}

$mysqli -> close ( ) ;
?>

例子2 - 過程式風格

返回一個對像數組，這些對象表示結果集中的字段，然後打印每個字段的名稱、表和最大長度：

 <?php
$con = mysqli_connect ( "localhost" , "my_user" , "my_password" , "my_db" ) ;

if ( mysqli_connect_errno ( ) ) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error ( ) ;
  exit ( ) ;
}

$sql = "SELECT Lastname, Age FROM Persons ORDER BY Lastname" ;

if ( $result = mysqli_query ( $con , $sql ) ) {

  // 獲取所有字段的字段信息
  $fieldinfo = mysqli_fetch_fields ( $result ) ;

  foreach ( $fieldinfo as $val ) {
    printf ( "Name: %s\n" , $val -> name ) ;
    printf ( "Table: %s\n" , $val -> table ) ;
    printf ( "Max. Len: %d\n" , $val -> max_length ) ;
  }
  mysqli_free_result ( $result ) ;
}

mysqli_close ( $con ) ;
?>