If Else in html web page

Question

I'm trying to set up an html web page that depends on the user entering a certain word in one text box to make another text box display a different word. Ultimately the use of this feature will become more complex but for now I just want to make that simple routine work. I've written code but it doesn't seem to follow the logic. When I click on the button no matter what is in text1 both text1 and text2 show "Dog" and "Cat" respectively. Here's my code that isn't working:

enter code here
<head>
<title></title>
</head>
<body> 
<script type="text/javascript">
  function myFunction() {
      if (Text1.value = "Dog") 
      {
          Text2.value = "Cat";
      }
      else
      {
          Text2.value = "Mouse";
      }
  }
</script>
<br><br><br><br>
<font size=6 face=arial color=#336699>
<b>TestRoutine</b>
<br><br>
</font>
<input id="Button1" type="button" value="button" onclick="myFunction()"> 
<input id="Text1" type="text" />
<input id="Text2" type="text" />
</body>
</html>

Quentin · Accepted Answer · 2013-11-25 00:03:29Z

2

You never define Text1. You want var Text1 = document.getElementById('Text1');
= is an assignment. You need to use === for a comparison (or == for a comparison with type coercion)

answered Nov 25, 2013 at 0:03

Quentin

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Comments

Charles · Accepted Answer · 2013-11-25 00:20:59Z

2

You need to replace Text1.value and Text2.value with:

document.getElementById("Text1").value

and

document.getElementById("Text2").value

respectively.

Also, when making comparisons in your if statement, you should you === instead of = to actually compare the values.

Edit: You should actually use === instead of ==.

edited Nov 25, 2013 at 0:20

answered Nov 25, 2013 at 0:03

Charles

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2 Comments

Halcyon Over a year ago

DOMNode.value is always a string so you don't need the type coercion from ==. Use ===.

Charles Over a year ago

Thanks, I still don't have a full understanding of when to use === vs ==. The latter == would still work in this scenario, but I guess the former is better.

Kazez · Accepted Answer · 2013-11-25 01:17:02Z

0

I fixed it thanks to the suggestions and tried not to fix the parts that i do not like.

<html>
<head>
<title></title>
</head>
<body> 
<script type="text/javascript">
  function myFunction() {
      if (document.getElementById("Text1").value === "Dog") 
      {
          document.getElementById("Text2").value = "Cat";
      }
      else
      {
          document.getElementById("Text2").value = "Mouse";;
      }
  }
</script>
<br><br><br><br>
<font size=6 face=arial color=#336699>
<b>TestRoutine</b>
<br><br>
</font>
<input id="Button1" type="button" value="button" onclick="myFunction()"> 
<input id="Text1" type="text" />
<input id="Text2" type="text" />
</body>
</html>

answered Nov 25, 2013 at 1:17

Kazez

1

3 Comments

user3029051 Over a year ago

Great. Now I want to make the if statement link to another page instead of filling Text2. The other page would be something like FileDownload.htm.

user3029051 Over a year ago

I found it!parent.document.location.href = "Docx.htm";

user3029051 Over a year ago

What I meant to say is that I found it.

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