JavaScriptBootCamp/34_errors.html at master · theBrainFordAI/JavaScriptBootCamp · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
<!DOCTYPE html>
<html>
<body>

<h2>JavaScript try catch</h2>

<p>Please input a number between 5 and 10:</p>

<input id="demo" type="text">
<button type="button" onclick="myFunction()">Test Input</button>
<p id="p01"></p>

<script>
function myFunction() {
  const message = document.getElementById("p01");
  message.innerHTML = "";
  let x = document.getElementById("demo").value;
  try {
    if(x == "")  throw "empty";
    if(isNaN(x)) throw "not a number";
    x = Number(x);
    if(x < 5)  throw "too low";
    if(x > 10)   throw "too high";
  }
  catch(err) {
    message.innerHTML = "Input is " + err;
  }
}
</script>

<h2>JavaScript Errors</h2>

<p>You cannot use the value of a non-existing variable:</p>

<p id="demo1"></p>

<script>
let x = 5;
try {
  x = y + 1;
}
catch(err) {
  document.getElementById("demo1").innerHTML = err.name;
}
</script>

</body>
</html>