While loop will execute a code block if the statement is true.
var i=0;var sum=0;while (i < 10) { sum += i; i++; } alert(sum);//55
var i=0;var sum=0;do { sum += i; i++; }while (i < 10)
var i=0;var sum=0;while (i < 10) { sum += i; if (i == 4) break; i++; } alert(i);//4 alert(sum);//0+1+2+3+4=10
We must put i++ before the if statement, otherwise, if the i is not increased, the while loop will keep running forever till the browser collapse.var i=0;var sum=0;while (i < 10) { i++; if (i == 4) continue; else sum += i; } alert(i);//10 alert(sum);//51