verify integer value in javascript

Question

In my application, I am taking a value for username. If that value is 0, then I have to run some code. But how should I write the if block?

 var userName=document.getElementById("member").value;

The above statement will return 0 (zero). Can anybody write the if statement for me? Thank you in advance.This is the entire code

var userName=document.getElementById("member").value;
    var password=document.getElementById("password").value;

    if(userName==="0"){
        var div4 = document.getElementById("errorMessage");
        var text1 = "insert userName.";
        div4.style.display = "block";
        div4.style.color = "red";
        div4.style.fontSize = "65%";
        div4.innerHTML = text1;

KooiInc · Accepted Answer · 2012-05-03 09:18:35Z

1

Additional to the other answers: you could check for the value 0 this way

if (Number(userName) === 0)

With the advantage that if the user fills the username field with whitespace only (spaces, tabs etc) it will still evaluate to true (that's because the Number conversion trims the parameter value).

answered May 3, 2012 at 9:18

KooiInc

124k32 gold badges145 silver badges181 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Dan D. · Accepted Answer · 2012-05-03 05:55:43Z

0

As the value of userName is of type string, you could use:

if (userName === "0") {
  ...
}

answered May 3, 2012 at 5:55

Dan D.

75k15 gold badges111 silver badges129 bronze badges

Comments

Blender · Accepted Answer · 2012-05-03 05:55:55Z

0

The .value attribute will return a string.

In this case, you can compare the value of userName to 0, the string:

if (userName == '0') {
  ...
}

answered May 3, 2012 at 5:55

Blender

300k55 gold badges462 silver badges511 bronze badges

3 Comments

user1305398 Over a year ago

yes I am aware about this, and this should work for sure.but unexpectedly its not working.I have edited the question a bit.Look if you can find out any mistakes.

Blender Over a year ago

What's the error? The code you posted seems fine. Post the HTML as well.

user1305398 Over a year ago

Well it is working now, but for this if(userName=="0"). Intially it wasnt working maybe because I hadnt cleared cache.

Collectives™ on Stack Overflow

verify integer value in javascript

3 Answers 3

Comments

Comments

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related