Nested if - JavaScript

Question

I want the code to read the input value for Bz and give a greeting along with the answer from the equation. This is what I have this far. It's not giving a 'greeting' after the computation. Help?

  <html>
  <body>

<form id="function" onsubmit="return false" oninput="o.value = 3.21 + (9.63 * parseInt(Bz.valueAsNumber))">
    3.21+(9.63 *<input name="Bz" type="number" step="any">) =
   <output name="o" for="intial set Bz">0</output>&nbsp;nT

</form>

<div id="mys1"></div>

<script language="JavaScript">   
 function myMath() 
 {
    var Bz;
    var greeting; 
    if(Bz>-50)
    {
         if (Bz>-30)
         {
               greeting = "None"; 
         }
         else  
         {
               greeting = "Small ";
         }
         else 
         { 
               if (Bz> -80) 
               {
                     greeting = "Mild ";
               }
               else 
               {
                     greeting = "Large ";
               }
          }
     }
 document.getElementById("mys1").innerHTML= greeting;
 };  
</script>

</body>
</html>

There's no `else..else` construction in JS, it should be `if..else..if..else`... — Teemu, Jun 18 '15 at 17:17
@Teemu There are two if statements. The indentation is all messed up. — Bill the Lizard, Jun 18 '15 at 17:18
You've got a syntax error, missing the closing `}` for the first (outer) `if` block. Please check your error console before posting, and fix your indentation. — Bergi, Jun 18 '15 at 17:19
@BilltheLizard Yep, but there is two sequential `else` blocks in the code. — Teemu, Jun 18 '15 at 17:19
@Teemu Ah yes, you're right. I think he's missing a `}` too. — Bill the Lizard, Jun 18 '15 at 17:21

pablito.aven · Answer 1 · 2015-06-19T13:44:49.683

0

Where are you calling your function myMath() from? I guess it is not being fired.

Also, the way you wrote your ifs statements is pretty ugly. This would be much nicer:

if(Bz>-30)
{
    greeting = "Small";
}
else if(Bz>-50)
{
    greeting = "Mid ";
}
else if(Bz>-80)
{
    greeting = "Large";
}
else
{
    greeting = "None";
}

Beware that I wrote this trying to guess what greeting message you actually want. Notice that if the first condition is satisfied, the other conditions will not even be checked at all.

edited Jun 19 '15 at 13:44

answered Jun 18 '15 at 17:42

pablito.aven

1,135
1
11
29

I forgot one line of code after the equation:
– maebee_me Jun 18 '15 at 17:54
1

Ok, then the problem is that your `if` are wrong. If you explain me what greeting you want in which case I would write the ifs for you. Also, are there any errors in your console? If there are you should add them to your post too – pablito.aven Jun 18 '15 at 18:09
There are no errors showing after I took it out of the format I had initially. For Bz > -80, I wanted it to greet Large. For Bz > -50, Mild. Bz > -30, Small. It was suppose to analysis the input and greet determining the range it fit best with. – maebee_me Jun 19 '15 at 12:39
@maebee_me Alright, I have fixed the code in the answer. Please check it out. If the value is any value bigger than -30, greeting is small. If it is between -50 and -30, the value is mid. If it is between -80 and -50, it is Large. If it is less than -80(Because it doesn't fit in any of the other cases), then the greeting is "None". I hope this helped you, please let me know if you still can't do it. – pablito.aven Jun 19 '15 at 13:47
regardless of the number, the only thing that shows is 'None'. – maebee_me Jun 19 '15 at 14:10
I added a new answer, please check it out and upvote me if it works. – pablito.aven Jun 19 '15 at 14:20

score 0 · Accepted Answer · answered Jun 19 '15 at 14:20

0

I found your problem. Bz value is not being loaded. Seting input name attribute will not store the value into a variable. That attribute is for form submission.

What you should do is:

function myMath() 
 {
    var Bz = $("input[name='Bz']").val();
    ...
    ...
    ...
 }

answered Jun 19 '15 at 14:20

pablito.aven

1,135
1
11
29

'$' is jquery. I don't have that in my script. Is there any other way to do it without jquery? – maebee_me Jun 19 '15 at 14:50
So, can't you use JQuery for some reason? [Here](http://stackoverflow.com/questions/11563638/javascript-get-input-text-value) you can find how to target the desired input without JQuery. If you can assign an ID to it, it is just `var Bz = document.getElementById("your_input_id").value;` – pablito.aven Jun 19 '15 at 15:12
1

Got it! Thanks for the help. – maebee_me Jun 19 '15 at 15:33

Nested if - JavaScript

2 Answers2