vedi se ti può servire

codice:
<HTML>
<HEAD>
<META NAME="GENERATOR" Content="Microsoft Visual Studio 6.0">
<TITLE></TITLE>
<SCRIPT ID=clientEventHandlersJS LANGUAGE=javascript>
<!--

function button1_onclick() {
	/*
	var tabella = document.getElementById("Tabella1");
	if(!tabella) return;
	var i, j;
	
	
	
	var tabella_n = tabella.childNodes.length;
	
	for(i = 0; i < tabella_n; i++) 
		if(tabella.childNodes[i].tagName != undefined)
			alert(tabella.childNodes[i].tagName);
	
	
	var tb = tabella.getElementsByTagName("TBODY")[0];
	var r = -1, c = -1;
	for(i = 0; i < tb.childNodes.length; i++) 
		if(tb.childNodes[i].tagName != undefined)
		{	
			//alert(tb.childNodes[i].tagName);
			r++; c = -1;
			for (j = 0; j < tb.childNodes[i].childNodes.length; j++)
			{
				if(tb.childNodes[i].childNodes[j].tagName != undefined)
				{	
					c++;
					alert(r + ", " + c + ": " + tb.childNodes[i].childNodes[j].innerHTML);
				}
			}
	
		}
	
	
	
	
	return;
	*/
	
	var tb = document.getElementById("Tabella1");
	if(!tb) return;
	var i, j;
	
	var righe = tb.getElementsByTagName("TR");
	for(i = 0; i < righe.length; i++) 
	{
		var colonneTD = righe[i].getElementsByTagName("TD");
		for(j = 0; j < colonneTD.length; j++) 
			alert(i + ", " + j + ": " + colonneTD[j].innerHTML);
		
		var colonneTH = righe[i].getElementsByTagName("TH");
		for(j = 0; j < colonneTH.length; j++) 
			alert(i + ", " + j + ": " + colonneTH[j].innerHTML);

	}

}

//-->
</SCRIPT>
</HEAD>
<BODY>

<table border="1" id="Tabella1" cellpadding="2" cellspacing="0">
	<tr>
		<th width="30" height="30">a1</th>
		<th width="30" height="30">b1</th>
		<th width="30" height="30">c1</th>
		<th width="30" height="30">d1</th>
	</tr>
	<tr>
		<td width="30" height="30">a2</td>
		<td width="30" height="30">b2</td>
		<td width="30" height="30">c2</td>
		<td width="30" height="30">d2</td>
	</tr>
	<tr>
		<td width="30" height="30">a3</td>
		<td width="30" height="30">b3</td>
		<td width="30" height="30">c3</td>
		<td width="30" height="30">d3</td>
	</tr>
	<tr>
		<td width="30" height="30">a4</td>
		<td width="30" height="30">b4</td>
		<td width="30" height="30">c4</td>
		<td width="30" height="30">d4</td>
	</tr>
</table>



<INPUT type="button" value="Button" id=button1 name=button1 LANGUAGE=javascript onclick="return button1_onclick()">
</BODY>
</HTML>