Javascript if statement

Cork Skate · 07-01-2005 11:27pm #1

Lads, i convert a string with

variable1 = parseFloat(document.form.textfield.value);

then i pass variable1 to a function

functionname(variable1)

and then i check

if (variable1 >= 100)
{
alert("it works");
}
else if (variable1>=50)
{
alert("it works aswell");
}
else (variable1 >= 25)
{
alert("it works all the time");
}

and then

whatever = functionname

Why doesn't it work ??
It wont go through the if statement ???

Rabies · 07-01-2005 11:32pm

Should it be

functionname(variable1)

and then i check

if (variable1 >= 100)
{
alert("it works");
}
else if (variable1>=50)
{
alert("it works aswell");
}
else if (variable1 >= 25)
{
alert("it works all the time");
}
else
{
whatever = functionname;
}

Cork Skate · 08-01-2005 12:08am

No ... it is a javascript script in html ... not php

It is just the if statement is not check the number that it is being given

if the condition is true it doesn't execture the alert

if (variable1 >= 100)
{
alert("it works");
}

richardo · 08-01-2005 10:38am

Probably a silly question, but have you declared variable1 as a variable?

variable1 = parseFloat(document.form.textfield.value);

should be

var variable1 = parseFloat(document.form.textfield.value);

Cork Skate · 09-01-2005 3:22am

richardo wrote:

Probably a silly question, but have you declared variable1 as a variable?

variable1 = parseFloat(document.form.textfield.value);

should be

var variable1 = parseFloat(document.form.textfield.value);

Yeah ..... like this

var variable1;

variable1 = parseFloat(document.form.textfield.value);

that'll do wont it ?

Cork Skate · 09-01-2005 5:03am

Lads, the same piece of code but a different problem

I am getting a mesage saying that line 101, the text field document.results.comorgper.value is null or not an object ...

it is an object because i have had it working previously (something written to it) and this piece of code check if it has something in it ...

if (document.results.comorgper.value=="")
{
alert("Please enter a percentage result");
document.results.comorgper.focus();
}

Actually ... i would mind mailing it to someone to have a look at it if possible !?! I'll be at it all today (sun)

Cork Skate · 09-01-2005 2:23pm

I have created a new page and still get errors ....

<html>
<head><title>Test Page 106</title></head>
<script language="JavaScript">
function testif()
{
var number = 0,
var letter = 5;
if (number = 0)
{
alert("Thisi s the first part of the if");
if (letter = 5)
{
alert("Thisi s the second part of the if");
}
}
}
</script>
<body>
<input type="button" value="Submit" onClick="testif()">
</body>
</html>

It now says that ...

line 7 char 2 Expected Identifier
line 19 char 1 Object Expected

richardo · 09-01-2005 2:35pm

Cork Skate wrote:

I have created a new page and still get errors ....

It now says that ...

line 7 char 2 Expected Identifier
line 19 char 1 Object Expected

Two problems there:
var number=0, should be var number =0; [semi-colon, not comma]

and when testing for equality, use '==' NOT '='
so change 'if (number=0)' to 'if (number==0)' [and of course the test for 'letter']

Hope that helps.........

Cork Skate · 09-01-2005 2:49pm

Ricardo ... thanks a million. I am totally new to javascript so am learning as i go along. !! Cheers again !!

richardo · 09-01-2005 2:59pm

Glad to be of some help. We ALL had to start somewhere. And if you don't try, you'll get nowhere fast!

Cork Skate · 09-01-2005 3:06pm

Ricardo ... thisis probably obvious but when that if is finished ... it does move to the next one right .... i dont have to return; at the end of the if i am guessing ??

richardo · 09-01-2005 3:17pm

At the end of an IF condition, the next statment will be processed.
In your example, you have nested the IFs so if number != 0 then that is the end of the function. The test for 'letter' will only occur if number does equal 0.
I always like to indent my code. It makes debugging a LOT easier:

function testif()
   {
   var number = 0;
   var letter = 5;
   if (number == 0)
      {
       alert("This is the first part of the if");
       if (letter == 5)
          {
          alert("This is the second part of the if");
          }
     }
  }

Any help??

Cork Skate · 09-01-2005 3:27pm

Yeah, its good .... but i have another problem now ...

if (document.results.comorgche.checked==true)
{
if (document.results.comorgper.value=="")
{
alert("Please enter a percentage result");
document.results.comorgper.focus();
}

it is saying that document.results.comorgper.value is null or not an object

but it worked fine when i had

if (document.results.comorgche.checked==true && document.results.comorgper.value=="")

Cork Skate · 09-01-2005 5:09pm

Sorry ... i had the

</form>

in the wrong place ... oopps

It works fine now !!

Javascript if statement

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