Equating strings with true in if

Question

Probably I am confused or something but I am not able to understand this silly scenario.

if("true"){
  console.log("Above is true");
}
else{
  console.log("Above is false");
}

In the above case the console is nicely printing Above is true. Which makes total sense. But when I am doing:

if("true" == true){
  console.log("Above is true");
}
else{
  console.log("Above is false");
}

I am seeing that Above is false is getting printed in the console.

I am using a loose equality operator here and even after coercion true will convert to "true" so it should print Above is true but is not. What am I missing?

"true" is string and true is a boolean value so those are not equal — Jay Shankar Gupta, Mar 03 '18 at 08:51
@JayShankarGupta but I am using loose equality operator here. Just like `0 == false` is true but `0 === false` is not. — void, Mar 03 '18 at 08:52
@Striped No. `""` is also a string, and it is also `!== undefined` but `if("")` is false. `false, "", 0, NaN, null, undefined` these are the falsy values. **everything else** will be considered truthy. This has nothing to do with comparison to `undefined` — Thomas, Mar 03 '18 at 08:58

score 4 · Accepted Answer · answered Mar 03 '18 at 08:56

4

check out this article https://javascriptweblog.wordpress.com/2011/02/07/truth-equality-and-javascript/

//EQUALITY CHECK...
"true" == true; 
//HOW IT WORKS...
//boolean is converted using toNumber
"true" == 1;
//string is converted using toNumber
NaN == 1; //false!

answered Mar 03 '18 at 08:56

user3666653

188
1
7

`//string is converted using toNumber` - Nope... -> [11.9.3.7](https://www.ecma-international.org/ecma-262/5.1/#sec-11.9.3) (11.9.3.5 is not fulfilled) – Andreas Mar 03 '18 at 09:00

score 0 · Answer 2 · answered Mar 03 '18 at 08:54

0

"If one of the operands is Boolean, the Boolean operand is converted to 1 if it is true and +0 if it is false."

true == "true"; //false
true == "1"; //true
false == "false"; //false
false == ""; //true
false == "0"; //true

Equating strings with true in if

2 Answers2