Java script get table cell values and get cell text boxes values

How can I get table cell values and cells text boxes values?That means getting childNodes values using java script.This is easy using core javascripts.Only using 2 for loops.First loop is going to get rows by rows.And other for loop is going each colomn/cells while running the loop of row.This is easy to understand by following simple example.

Get Table cell values using Javascript
This is my table.

ID Name Country Marks Rank
1 Smith US 4
2 John England 2
3 William Australia 3
4 Michael Germany 1

Now we’ll get the values.

         // Get table object
	var myTable = document.getElementById('student_table').tBodies[0];
         // first loop for each row
        for (var r=0, n = myTable.rows.length; r < n; r++) {
                       // this loop is getting each colomn/cells
			for (var c = 0, m = myTable.rows[r].cells.length; c < m; c++) {
			   if(myTable.rows[r].cells[c].childNodes[0].value){
				   	// get student names
					var StudentName = myTable.rows[r].cells[1].innerHTML;
					alert(StudentName);
					// get student marks in each text boxes
			   		var marks = myTable.rows[r].cells[c].childNodes[0].value;
			   		alert(marks);
			   }
            }
        }

That's only.

Additional Notes

Get table row count.

var rowCount = document.getElementById('student_table').tBodies[0].rows.length;

Get table column count.

var columnCount = document.getElementById('student_table').rows[0].cells.length;

Get table cell html.

var cellHtml = document.getElementById('student_table').tBodies[0].rows[r].cells.innerHTML;

Get table cell text.

var cellText = document.getElementById('student_table').tBodies[0].rows[r].cells.Text;