Clear rows in knockout.js Cart Editor example

Question

I am trying the knockout js example of cart editor given here

I want to delete all the rows added by the user as soon as the java script alert comes. I thought setting the cartLine array to nothing would do the job but it didn't work. I tried this:

    self.save = function() {
    cartLine([])
    var dataToSave = $.map(self.lines(), function(line) {
        return line.product() ? {
          productName: line.product().name,
          quantity: line.quantity()
        } : undefined
    });
    alert("THANK YOU FOR YOUR ORDER!");  
};

But it didn't help. Please correct me if I am wrong. Thanks.

Update:

self.save = function() {
  var dataToSave = $.map(self.lines(), function(line) {
    return line.product() ? {
      productName: line.product().name,
      quantity: line.quantity()
    } : undefined
  });
  self.lines([]);
  self.addLine = function() { self.lines.push(new CartLine()) };
 alert("THANK YOU FOR YOUR ORDER!");
  self.addLine = function() { self.lines.push(new CartLine()) }; //didn't work
};

Answer 1

The lines field of the Cart object contains all cart lines. It's used to generate dataToSave, then you can clear it:

self.save = function() {
var dataToSave = $.map(self.lines(), function(line) {
    return line.product() ? {
      productName: line.product().name,
      quantity: line.quantity()
    } : undefined
});
self.lines([]); // clear cart lines
alert("THANK YOU FOR YOUR ORDER!");
self.addLine(); // add a new line