PHP mysqli_fetch_fields()用法及代码示例

定义和用法

PHP 结果对象(属于 mysqli_result 类)表示 MySQL 结果，由 SELECT 或 DESCRIBE 或 EXPLAIN 查询返回。

mysqli_fetch_fields() 函数接受一个结果对象作为参数，并返回一个对象数组，每个对象代表结果中的一个字段。

用法

mysqli_fetch_fields($result);

参数

Sr.No	参数及说明
1	result(Mandatory) 这是一个表示结果对象的标识符。

返回值

PHP mysqli_fetch_fields() 函数返回一个对象数组，其中每个对象都包含给定结果中某个字段的定义信息。如果没有信息，此函数返回 FALSE。

返回数组的对象包含以下属性 $minus;

• name

• orgname

• table

• orgtable

• max_length

• length

• charsetnr

• flags

• type

• decimals

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

下面的例子演示了 mysqli_fetch_fields() 函数的用法(程序风格)

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

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

   //Retrieving the contents of the table
   $res = mysqli_query($con, "SELECT * FROM myplayers");

   //Fetching all the fields
   $info = mysqli_fetch_fields($res);
   foreach ($info as $ele) {
      print("ID:".$ele->name."\n");
      print("First_Name:".$ele->table."\n");
      print("Last_Name:".$ele->max_length."\n");
      print("Place_Of_Birth:".$ele->charsetnr."\n");
      print("Country:".$ele->flags."\n");
      print("Country:".$ele->type."\n");
      print("\n");
   }
   //Closing the statement
   mysqli_free_result($res);

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

这将产生以下结果 -

Table Created.....
Record Inserted.....
ID:ID
First_Name:myplayers
Last_Name:1
Place_Of_Birth:63
Country:32768
Country:3

ID:First_Name
First_Name:myplayers
Last_Name:8
Place_Of_Birth:33
Country:0
Country:253

ID:Last_Name
First_Name:myplayers
Last_Name:10
Place_Of_Birth:33
Country:0
Country:253

ID:Place_Of_Birth
First_Name:myplayers
Last_Name:8
Place_Of_Birth:33
Country:0
Country:253

ID:Country
First_Name:myplayers
Last_Name:11
Place_Of_Birth:33
Country:0
Country:253

示例

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

<?php
   //Creating a connection
   $con = new mysqli("localhost", "root", "password", "mydb");
 
   $con -> query("CREATE TABLE Test(Name VARCHAR(255), Age INT)");
   $con -> query("insert into Test values('Raju', 25),('Rahman', 30),('Sarmista', 27)");
   print("Table Created.....\n");

   $stmt = $con -> prepare( "SELECT * FROM Test WHERE Name in(?, ?)");
   $stmt -> bind_param("ss", $name1, $name2);
   $name1 = 'Raju';
   $name2 = 'Rahman';

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

   //Retrieving the result
   $result = $stmt->get_result();

   //Fetching all the rows as arrays
   $info = $result->fetch_fields();
   foreach ($info as $ele) {
      print("ID:".$ele->name."\n");
      print("First_Name:".$ele->table."\n");
      print("Last_Name:".$ele->max_length."\n");
      print("Place_Of_Birth:".$ele->charsetnr."\n");
      print("Country:".$ele->flags."\n");
      print("Country:".$ele->type."\n");
      print("\n");
   }
   //Closing the statement
   $stmt->close();

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