PHP mysqli_fetch_field_direct() 函数
PHP mysqli_fetch_field_direct() 函数
实例
返回结果集中某个单一字段（列）的 meta-data，并输出字段名称、表格和最大长度：
<?php
$con=mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$sql="SELECT Lastname,Age FROM Persons ORDER BY Lastname";
if ($result=mysqli_query($con,$sql))
{
// Get field information for "Age"
$fieldinfo=mysqli_fetch_field_direct($result,1);
printf("Name: %sn",$fieldinfo->name);
printf("Table: %sn",$fieldinfo->table);
printf("max. Len: %dn",$fieldinfo->max_length);
// Free result set
mysqli_free_result($result);
}
mysqli_close($con);
?>
$con=mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$sql="SELECT Lastname,Age FROM Persons ORDER BY Lastname";
if ($result=mysqli_query($con,$sql))
{
// Get field information for "Age"
$fieldinfo=mysqli_fetch_field_direct($result,1);
printf("Name: %sn",$fieldinfo->name);
printf("Table: %sn",$fieldinfo->table);
printf("max. Len: %dn",$fieldinfo->max_length);
// Free result set
mysqli_free_result($result);
}
mysqli_close($con);
?>
定义和用法
mysqli_fetch_field_direct() 函数从结果集中取得某个单一字段（列）的 meta-data，并作为对象返回。
语法
mysqli_fetch_field_direct(result,fieldnr);
| 参数 | 描述 |
|---|---|
| result | 必需。规定由 mysqli_query()、mysqli_store_result() 或 mysqli_use_result() 返回的结果集标识符。 |
| fieldnr | 必需。规定字段号。必须介于 0 和 字段数-1 之间。 |
技术细节
| 返回值： | 返回包含字段定义信息的对象。如果没有可用信息则返回 FALSE。该对象有下列属性：
|
|---|---|
| PHP 版本： | 5+ |
PHP MySQLi 参考手册