how get the cell value?

Suite and Optimus Suite 5
#1

Hi all, how are get the cell value ??
for example, i have var selId = areaTrabajoCalculos.getSelectedId(); , and I need the cell value, in web I find this solution but doesn’t work

“alert(areaTrabajoCalculos.cells(selId,0));”
what is my error?,

thanks for your time
best regards

#2 
alert(areaTrabajoCalculos.cells(selId,0).getValue())

docs.dhtmlx.com/doku.php?id=dhtm … of_excells