增加刷新浏览器的价值不应那样做

Question

enter code here我创建了一个基本的投票系统。该数据库具有3列col1，col2，col3。 像“提交按钮_1”上的php代码的col1值将更新为+1。 因此，我单击了数据库中更新的button_1值。但是，当我刷新浏览器时，无需单击button_1，数据库col1的值就会增加。

   <?php
     include "vote.des.php";
     $con = mysqli_connect("localhost","root","","voting");

    if(isset($_POST['ele'])){
      header("Loction: vote.php");
      $vote_ele = "update votes set ele = ele + 1";
      $run = mysqli_query($con,$vote_ele);

   }

   if(isset($_POST['comp'])){
      header("Loction: vote.php");       
      $vote_comp = "update votes set comp = comp + 1";
      $run = mysqli_query($con,$vote_comp);

    }

    if(isset($_POST['phy'])){
    header("Loction: vote.php");
    $vote_phy = "update votes set phy = phy + 1";
    $run = mysqli_query($con,$vote_phy);

     }
     mysqli_close($con);
   ?>

输出必须是： 当我单击按钮时，值应该被更新。当我不单击按钮时，该值不应更新。在刷新浏览器时，该值不应更新。