PHP homework 2.3 judging students’ grade

Time:2022-4-30

requirement


Use ajax to calculate the level in the background and output it to the PHP page. The valid input is 0 ~ 100.

design sketch


PHP homework 2.3 judging students' grade

index. PHP code


<!DOCTYPE html>
<html>

<head>
  <meta charset="UTF-8" />
  < title > judge the grade of students < / Title >
</head>
<link rel="stylesheet" />
<style>
  body {
    background-color: #dedede;
  }

  .main {
    border: 7px dotted #00bcff;
    width: 555px;
    margin: 222px auto;
    padding: 0 28px;
    font-size: 28px;
  }

  h1 {
    text-align: center;
  }

  input {
    height: 30px;
    border: none;
  }

  #cj {
    color: red;
  }
</style>

<body>
  <div class="main">
    <h1>Student grade</h1>
    <p>Student Name: < input type = "text" placeholder = "please enter name" id = "name" / ></p>
    <p>
      Student score: < input type = "text" placeholder = "please enter grade" id = "num" onchange = "zl()" / >
    </p>
    <p>Student achievement: < span id = "CJ" > < / span ></p>
  </div>

  <script>
    function zl() {
      var num = document.getElementById("num").value;

      //1. create object
      var xmlhttp;
      if (window.XMLHttpRequest) {
        //IE7 +, Firefox, chrome, opera, Safari browser execution code
        xmlhttp = new XMLHttpRequest();
      } else {
        //IE6, IE5 browser execution code
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      }
      //2. Determine whether the object is ready
      xmlhttp.onreadystatechange = function() {
        if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
          document.getElementById("cj").innerHTML = xmlhttp.responseText;
        }
      };
      //3. Make a request
      xmlhttp.open("GET", "data.php?num=" + num, true);
      xmlhttp.send();
    }
  </script>
</body>

</html>

data. PHP code


<?php
$num = $_GET["num"];
switch (intval($num / 10)) {
  case 10:
    $str =   "A";
    break;
  case 9:
    $str = "A";
    break;
  case 8:
    $str = "B";
    break;
  case 7:
    $str = "C";
    break;
  case 6:
    $str = "D";
    break;

  case 5:
  case 4:
  case 3:
  case 2:
  case 1:
  case 0:

    $str = "E";
    break;
  default:
    $STR = "please enter the correct score";
}
Echo "$STR level";
?>