Javascript one line If else else if statement

Question

I know you can set variables with one line if else statements by doing var variable    condition     true block     else block   but I was wondering if there was a way to put an else if statement in there  Any suggestions would be appreciated  thanks everyone

User · Answer

This is use mostly for assigning variable, and it uses binomial conditioning eg.

var time = Date().getHours(); // or something

var clockTime = time > 12 ? 'PM' : 'AM' ;

There is no ElseIf, for the sake of development don't use chaining, you can use switch which is much faster if you have multiple conditioning in .js

User · Answer

I know this is an old thread  but thought I d put my two cents in  Ternary operators are able to be nested in the following fashion   var variable   conditionA   valueA    conditionB   valueB   conditionC   valueC   valueD      Example   var answer   value      foo    1        value      bar    2             value      foobar    3   0

User · Answer

tl dr Yes  you can    If a then a  else if b then if c then c b   else b  else null a   a    b    c   c b    b    null   a     a     b         c           c b            b         null  longer version Ternary operator    used as inline if-else is right associative  In short this means that the rightmost   gets fed first and it takes exactly one closest operand on the left and two  with a    on the right  Practically speaking  consider the following statement  same as above   a   a   b   c   c b    b   null The rightmost   gets fed first  so find it and its surrounding three arguments and consecutively expand to the left to another       a   a   b   c   c b    b   null                                      lt ---- RTL 1              1- -2---- -3                  lt - 2          1-  --2---------  -3---          lt - 3  1- -2-  --3--------------------   result  a   a    b    c   c b    b    null   This is how computers read it    Term a is read  Node  a Nonterminal   is read  Node  a   Term a is read  Node  a   a Nonterminal   is read  Node  a   a   Term b is read  Node  a   a   b Nonterminal   is read  triggering the right-associativity rule  Associativity decides  node  a   a    b   Term c is read  Node  a   a    b   c Nonterminal   is read  re-applying the right-associativity rule  Node  a   a    b    c   Term c b  is read  Node  a   a    b    c   c b  Nonterminal   is read  Node  a   a    b    c   c b    Term b is read  Node  a   a    b    c   c b    b Nonterminal   is read  The ternary operator    from previous scope is satisfied and the scope is closed  Node  a   a    b    c   c b    b    Term null is read  Node  a   a    b    c   c b    b    null No tokens to read  Close remaining open parenthesis   Result is  a   a    b    c   c b    b    null    Better readability The ugly oneliner from above could  and should  be rewritten for readability as   Note that the indentation does not implicitly define correct closures as brackets    do   a     a     b         c           c b            b         null  for example return a   some lengthy variable name  gt  another variable            quot yep quot             quot nop quot   More reading Mozilla  JavaScript Conditional Operator Wiki  Operator Associativity  Bonus  Logical operators var a   0    1 var b   20 var c   null    x  gt   console log  b is   x   return true     return true here   a    amp  amp  a      b        amp  amp  c          amp  amp  c b     if this returns false     b is processed            b          null  Using logical operators as in this example is ugly and wrong  but this is where they shine     quot Null coalescence quot  This approach comes with subtle limitations as explained in the link below  For proper solution  see Nullish coalescing in Bonus2  function f mayBeNullOrFalsy      var cantBeNull   mayBeNullOrFalsy    42                        quot default quot  value   var alsoCantBe   mayBeNullOrFalsy   mayBeNullOrFalsy   42     ugly            Short-circuit evaluation false  amp  amp   anything     is short-circuit evaluated to false  true     anything      is short-circuit evaluated to true   Logical operators Null coalescence Short-circuit evaluation  Bonus2  new in JS Proper  quot Nullish coalescing quot  developer mozilla org Nullish coalescing operator function f mayBeNullOrUndefined  another      var cantBeNullOrUndefined   mayBeNullOrUndefined    42   another     37    nullish coalescing self-assignment   another   another    37    same effect         Optional chaining Stage 4 finished proposal https   github com tc39 proposal-optional-chaining https   developer mozilla org en-US docs Web JavaScript Reference Operators Optional chaining    before var street   user address  amp  amp  user address street    after var street   user address  street     combined with Nullish coalescing    before var street   user address     user address street      quot N A quot      after var street   user address  street     quot N A quot      arrays obj someArray   index      functions obj someMethod   args

User · Answer

You can chain as much conditions as you want  If you do   var x    false    1true     true   2true   2false      You will get x  2true   So it could be expressed as   var variable    condition     true block      condition   true block   false block

User · Answer

Sure  you can do nested ternary operators but they are hard to read   var variable    condition     true block      condition2     true block2     else block2

User · Answer

a      a    do something   a      b    do something   do something

User · Answer

In simple words   var x    day     yes      Good Day      day     no      Good Night

[javascript] Javascript one line If...else...else if statement

Examples related to javascript

Examples related to conditional-operator