javascript - else statement not working correctly - 


var question=prompt("what age?");  if (question == 14) {     alert("coupon 1") } if (question == 21) {     alert("coupon 2") } if (question == 30) {     alert("coupon 3") } if (question == 50){     alert ("coupon 4") } else {     alert("no coupon") }

if enter age 14, display "coupon 1" , after displays "no coupon". every if statement except last one, age 50. if enter age 50, coupon 4 , no "no coupon". not understand why this.

your if statements not connected, each 1 happening independent of others, means of cases being checked, if earlier 1 returns true. code more this: 

var question = prompt("what age?");     //check if 14     if (question == 14) {         alert("coupon 1")     }     //check if 21     if (question == 21) {         alert("coupon 2")     }     //check if 30     if (question == 30) {         alert("coupon 3")     }     //check if 50, else no coupon     if (question == 50){         alert ("coupon 4")     }     else {         alert("no coupon")     }

try changing use string of if elseif statements, means logic 1 continuous flow:

var question = prompt("what age?");         //check if 14         if (question == 14) {             alert("coupon 1")         }         //check if 21         else if (question == 21) {             alert("coupon 2")         }         //check if 30         else if (question == 30) {             alert("coupon 3")         }         //check if 50         else if (question == 50){             alert ("coupon 4")         }         //if none of above, no coupon         else {             alert("no coupon");         }

javascript - , many other languages - has built in syntax handles sort of if-elseif-else chain, called switch statement. can rewrite code using switch this: 

switch (prompt("what age?")) {     case 14:         alert("coupon 1");         break;     case 21:         alert("coupon 2");         break;     case 30:         alert("coupon 3");         break;     case 50:         alert("coupon 4");         break;     default:         alert("no coupon");         break; }

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