How to read a False Value

[Steve Dyke]

When rf1 = true and rf2 = false I still get the else condition result. What is the syntax for interpreting a false value?

 
if(rf1 && !rf2){
document.getElementById("rcsection").style.display = "inline";
}
else{
document.getElementById("rcsection").style.display = "none";
}
 

[Eric Pascarello]

Are you sure you have a false Boolean and not some other value that is really true?

How are your Booleans being declared?

Eric

[Varun Chopra]

Make sure rf1 = true and rf2 = false, then code will certainly go in if. See below:

boolean rf1 = true;
boolean rf2 = false;

if(rf1 && !rf2){
System.out.println("in if");
}
else{
System.out.println("in else");
}

Output:

in if

[Steve Dyke]

In my servlet I have:

 
session.setAttribute("rejflag1",new Boolean(ddConn.getRejflag1()));
session.setAttribute("rejflag2",new Boolean(ddConn.getRejflag2()));
 

Then in my JSP I have:

 
var rf1 = "${rejflag1}";
var rf2 = "${rejflag2}";
 

[Eric Pascarello]

Do yourself a favor and do

alert(typeof rf1);

Eric

[Steve Dyke]

Returned a value of string.

[Ben Souther]

Your code:

 var rf1 = "${rejflag1}";   

If you put quotes around it, then it's a string.
Non-empty strings are truthy.

Example:

if("false") alert("true");

Would show a popup with "true" in it.


Try removing the quotes.
[ November 20, 2008: Message edited by: Ben Souther ]

[Steve Dyke]

Thanks.

[Eric Pascarello]

Just to add what Ben said...

now do

  alert( new Boolean("false") );
  alert( new Boolean("boo") );
  alert( new Boolean("") );

JavaScript was doing the right thing treating your string as true. I recommend you to pick up JavaScript: The Good Parts and read it a few times. [It is short and packed with info, he explains this stuff]

Eric