Call break in nested if statements

Question

I have the following situation   IF condition THEN       IF condition THEN          sequence 1     ELSE         break           ENDIF     ELSE         sequence 3     ENDIF   What is the result of the break statement  Does it break the outer if statement  Because this is what I actually need

User · Answer

To make multiple checking statements more readable  and avoid nested ifs    var tmp    Test some email somewhereouttherebutnothere com     var posStartEmail   undefined  var posEndEmail   undefined  var email   undefined   do       if  tmp toLowerCase   substring 0 4       test     break         posStartEmail   tmp toLowerCase   substring 4  indexOf           posEndEmail   tmp toLowerCase   substring 4  indexOf            if  posStartEmail     -1    posEndEmail     -1    break         email   tmp substring posStartEmail 1 4 posEndEmail        if  email indexOf          -1    break        all checks are done - do what you intend to do      alert   All checks are ok        break     the most important break of them all    while true

User · Answer

Actually there is no c3 in the sample code in the original question   So the if would be more properly   if  c1  amp  amp  c2          sequence 1   else if   c1  amp  amp   c2          sequence 3

User · Answer

Just remove the break  since it is already inside first if it will not execute else  It will exit anyway

User · Answer

Javascript will throw an exception if you attempt to use a break  statement inside an if else   It is used mainly for loops   You can  break  out of an if else statement with a condition  which does not make sense to include a  break  statement   JSFiddle

User · Answer

In the most languages  break does only cancel loops like for  while etc

User · Answer

But there is switch-case     switch  true        case true          console log  Yes  its ture    Break from the switch-case            break      case false          console log  Nope  but if the condition was set to false this would be used and then break            break       default          console log  If all else fails            break

User · Answer

no it doesnt   break is for loops  not ifs   nested if statements are just terrible   If you can avoid them  avoid them    Can you rewrite your code to be something like  if  c1  amp  amp  c2          sequence 1   else if  c3  amp  amp  c2          sequence 3     that way you don t need any control logic to  break out  of the loop

User · Answer

I had a similar problem today and found refactoring the conditional logic into a separate function to help   I find it more readable than the labels and people are more comfortable with return than break  Inline functions are similar but the indentation can get a bit confusing   In your case it would look like this   function doThing       checkConditions          Rest of the code here    function checkConditions       if  c1        if  c2          return do1        else         return            else       return do3

User · Answer

You need that it breaks the outer if statement  Why do you use second else   IF condition THEN       IF condition THEN          sequence 1        ELSE sequence 4           break              ENDIF     ELSE         sequence 3     ENDIF  sequence 4

User · Answer

If you label the if statement you can use break   breakme  if  condition           Do stuff      if  condition2              do stuff       else          break breakme                Do more stuff     You can even label and break plain blocks   breakme           Do stuff      if  condition              do stuff       else          break breakme                Do more stuff     It s not a commonly used pattern though  so might confuse people and possibly won t be optimised by compliers   It might be better to use a function and return  or better arrange the conditions     function           Do stuff     if   condition1               Do stuff       else          return              Do other stuff

[javascript] Call break in nested if statements

Examples related to javascript