How to alert box in looping?

Answer 1

here is a possible code for a real situation :
var x = 0;
do {
alert(x);
x++;
}
while (x != 3)

Answer 2

you mean in javascript?

while(1) {
alert("hahha :P");
}

while 1 will always be repeated so you can't end this lol when you close one alert another will open

But I don't think you ment this while writing question... :D