Php/func mysqli field seek

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PHP mysqli field_seek()函数

MySQL PHP MySQLi参考

示例-面向对象的样式

将字段光标设置到结果集中的第二列(“年龄”),使用fetch_field()获取字段信息,然后打印该字段的名称,表和最大长度:

<?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)) {


  // Get field information for 
  second column
  $result = field_seek(1);
  $fieldinfo = $result -> fetch_field();


  printf("Name: %s\n", $fieldinfo -> name);
  printf("Table: %s\n", $fieldinfo -> table);

    printf("Max. Len: %d\n", $fieldinfo -> max_length);

    $result 
  -> free_result();
}


$mysqli -> close();
?>



在底部查看程序样式的示例。

定义和用法

field_seek()/ mysqli_field_seek()函数将字段光标设置为给定的字段偏移量。

句法

面向对象的样式:

$mysqli_result -> field_seek(fieldnr)

程序风格:

mysqli_field_seek(result, fieldnr)

参数值

参数 描述
result 需要。指定mysqli_query(),mysqli_store_result()或mysqli_use_result()返回的结果集标识符
fieldnr 需要。指定字段号。必须是0到之间的整数

number of fields -1

技术细节

返回值: 成功则为真。失败时为假
PHP版本: 5+

示例-程序风格

将字段光标设置到结果集中的第二列(“年龄”),使用mysqli_fetch_field()获取字段信息,然后打印该字段的名称,表和最大长度:

<?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)) {

  // Get field information for 
  second column
  mysqli_field_seek($result, 1);
  $fieldinfo = mysqli_fetch_field($result);

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


mysqli_close($con);

?>



MySQL PHP MySQLi参考