Using multiple conditions in ? : statements in javascript

Question

In need to check three conditions and assign a value to a variable according the condition.

if(a =="z1"){
   b = "one";
} else if(a =="z2"){
   b = "two";
} else if(a =="z3"){
   b = "three";
}

Is it possible to do it in JavaScript using ? : statement to make it as a single line code

Answer 1

Yes, you can use convert it to Conditional(ternary) operator.

var a = "z3";
var b = a == "z1" ? "one" : a == "z2" ? "two" : a == "z3" ? "three" : "" ;

console.log(b);

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FYI : For a better readability, I would suggest using if...else statement or use switch statement . Although you need to use parenthesis for nested ternary operator for avoiding problems in case complex operations.

Answer 2

var b = (a =="z1") ? "one" : ((a =="z2") ?"two":(a =="z3")?"three":null);

Don't forget that it's tough to read to read this quickly. It's quite ok to use for one if else block.

Answer 3

You can do this things:

b=( a=="z1"?"one":(a =="z2"? "two":(a =="z3"?"three":undefined)))

Answer 4

var b = a == "z1" ? "one" : ( a == "z2" ? "two" : ( a == "z3" ? "three" : undefined ) ) ;

a = "z1"

alert(a == "z1" ? "one" : ( a == "z2" ? "two" : ( a == "z3" ? "three" : undefined ) ) );

a = "z2"

alert(a == "z1" ? "one" : ( a == "z2" ? "two" : ( a == "z3" ? "three" : undefined ) ) );

a = "z3"

alert(a == "z1" ? "one" : ( a == "z2" ? "two" : ( a == "z3" ? "three" : undefined ) ) );

a = "z4"

alert(a == "z1" ? "one" : ( a == "z2" ? "two" : ( a == "z3" ? "three" : undefined ) ) );