Question

I want to create a JavaScript function that parses my HTML page, get the Table by it’s ID, and after that, add a class attribute to each <tr> as if the line is the 1st, I’ll add :
class=”line1″ to the <tr>
but if the line is the second, I’ll add class=”line2″ to the <tr>
How to do please

Answer 1

If I understand you corrrectly, you want to alternate the class names to get some kind of zebra style right?

var table = document.getElementById('yourTableId');
var rows = table.rows;
for(var i = 0, l = rows.length;i < l; i++) {
    rows[i].className = 'class' + ((i%2) + 1);
}

See the HTML DOM Table Object.