This demonstrates how to handle the paste of some portion of a spreadsheet (google spreadsheet, excel, ...). Listens for a paste event on a textarea and converts the pasted data into an matrix of cells.

paste-from-spreadsheet.js

var field = $('textarea.myTextarea');

var cells;

// listen to keydown on text field
field.on('keydown', function(e){
  
  // detect if it's a copy-paste action
  if(e.keyCode === 86){
    
    // It's a keydown event only, so wait 100ms for the field value to be updated
    setTimeout(function(){
      var data = field.val();
    
      // split line by line
      var lines = data.split('\n');
      
      // split each line by the tab character (charCode = 9)
      cells = _.map(lines, function(line){ 
        return line.split(String.fromCharCode(9));
      });
    }, 100);
    
    // cells contains an array of arrays
    // cells[line][row] gives the value of a cell
  }
});