Sample: dhtmlxGrid Copy to clipboard dhtmlxGrid main page
X
To select area in grid - hold left mouse button and move mouse to spread selection.
Press Ctrl+C to copy seleted rows into the clipboard, Ctrl+V to replace selected rows by rows from clipboard.
You can paste selected rows to Excell.
show clipboard

 
    
 mygrid.attachEvent("onKeyPress",onKeyPressed);
    ...
function onKeyPressed(code,ctrl,shift){
        
    if(code==67&&ctrl){
        mygrid.copyBlockToClipboard()
    }
        
    if(code==86&&ctrl){
        mygrid.pasteBlockFromClipboard()
    }
        
    return true;
}