|  | 
 mysqli_num_fields    (PHP 5) mysqli_num_fields     (no version information, might be only in CVS) result->field_count -- 
     Get the number of fields in a result
    DescriptionProcedural style: int mysqli_num_fields  ( object result) Object oriented style (property): class result  {  int field_count } 
      mysqli_num_fields() returns the number of fields from specified result set.
     返回值The number of fields from a result setExample| 例子 1. Object oriented style | 
<?php$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
 
 /* check connection */
 if (mysqli_connect_errno()) {
 printf("Connect failed: %s\n", mysqli_connect_error());
 exit();
 }
 
 if ($result = $mysqli->query("SELECT * FROM City ORDER BY ID LIMIT 1")) {
 
 /* determine number of fields in result set */
 $field_cnt = $result->field_count;
 
 printf("Result set has %d fields.\n", $field_cnt);
 
 /* close result set */
 $result->close();
 }
 
 /* close connection */
 $mysqli->close();
 ?>
 | 
 | 
 | 例子 2. Procedural style | 
<?php$link = mysqli_connect("localhost", "my_user", "my_password", "world");
 
 /* check connection */
 if (mysqli_connect_errno()) {
 printf("Connect failed: %s\n", mysqli_connect_error());
 exit();
 }
 
 if ($result = mysqli_query($link, "SELECT * FROM City ORDER BY ID LIMIT 1")) {
 
 /* determine number of fields in result set */
 $field_cnt = mysqli_num_fields($result);
 
 printf("Result set has %d fields.\n", $field_cnt);
 
 /* close result set */
 mysqli_free_result($result);
 }
 
 /* close connection */
 mysqli_close($link);
 ?>
 | 
 | 
 
     The above examples would produce the following output:
    
 |  |