Saturday, November 13, 2021


In this article, you will learn how to use the JavaScript loop statement to create a loop with various options.


The three most common types of loops are

  • for
  • while
  • do...while

for loop

for ([initialization]); [condition]; [final-expression]) {
   // statement
}

Here you can try this,

var inputs = document.getElementsByClassName('loopjavascript');
for (var i = 0; i < inputs.length; i++) {
    console.log(inputs[i].value);
}

<input type="text" name="test1" class="loopjavascript" value="loopjavascript 1">
<input type="text" name="test1" class="loopjavascript" value="loopjavascript 2">
<input type="text" name="test1" class="loopjavascript" value="loopjavascript 3">

<input type="text" name="test1" class="loopjavascript" value="loopjavascript 4">


while loop

while (condition)

{
  statement(s);
}

Here you can try this,

var i = 1;
    while (i < 10) 
    {
      console.log(i);
       i++; // i=i+1 same thing
    }

    Output:
    1 
    2 
    3 
    4
    5
    6
    7
    8
    9
Do..while loop

loops through a block of code once; then the condition is evaluated. If the condition is true, the statement is repeated as long as the specified condition is true.


do {
    // Code to be executed
}
while(condition);

Here you can try this,

var i = 1;
do {
    document.write("<p>The number is " + i + "</p>");
    i++;
}
while(i <= 5);