php - PHP 中的 VB if 语句

Question

我需要帮助将以下 Visual Basic 语句转换为 PHP 等效语句:

If Not IsNumeric(siteid) Then

    dr = GetDataReader("SELECT siteid FROM nwsite WITH (NOLOCK) WHERE mac_address = '" & siteid & "'")

    If Not dr.HasRows Then

      Response.Write(sep & siteid & "=" & siteid)

      sep = ","

    End If

    If Not dr Is Nothing Then

      dr.Close()

    End If

  End If

我最需要有关 If 语句的帮助。

谢谢

Answer 1

参见 here for the docs you need to check , 还有 here

看起来像你also need to learn how to use mySQL in PHP

代码相对简单，在其最简单的步骤中 - 几乎是一行一行地帮助您了解向 PHP 的转换(有更好的实现):

$siteid = 1; // where 1 is the value of siteid, PHP vars are prefixed with '$'


// you also could do 
//  if(!isset($siteid){
//  if(!$siteid){

if(!is_numeric($siteid){
  // there is no site ID, so get it from the DB

  // Make a MySQL Connection
  mysql_connect("localhost", "user", "password") or die(mysql_error());
  mysql_select_db("dbname") or die(mysql_error());

  // Run your query
  $result = mysql_query("SELECT siteid FROM nwsite WITH (NOLOCK) WHERE mac_address = ".$siteid) 
  or die(mysql_error());  

  if(mysql_num_rows($result)>0){
    // rows returned
    //assuming only one row is returned, with your siteid value
    $row = mysql_fetch_array( $result );
    $siteid=$row['siteid'];    
  }else{
    // no rows returned
    // do something
  }

}else{
 // $siteid is already a valid value
}