Should I be updating the data source or the control?

Question

I'm working in WinForms C#.NET

I have a form that I manually created the databindings for like so: txtDueDate.DataBindings.Add(new Binding("Text", bindingSource, "DueDate", true, DataSourceUpdateMode.OnPropertyChanged));

My question is, to update my form (UI and underlying datasource) should I be updating the underlying data source ((BusinessObject)(bindingSource.Current).DueDate = 12-12-12), or should I be updating the control value (txtDueDate.Text = 12-12-12)?

I don't seem to be getting consistent results with some of my controls (especially combo boxes), so I was wondering which is the correct way to do this.

Edit:

I think I figured it out.  In case anyone else is looking for this, update the control, the form dataSource gets updated "OnPropertyChanged".  So whenever you update the control, it fires back into the data source.  

Answer 1

I think I figured it out.  In case anyone else is looking for this, update the control, the form dataSource gets updated "OnPropertyChanged".  So whenever you update the control, it fires back into the data source.  

I'm glad you figure it out. Base on my understanding, you can also update the control value through update underlying code. For example,

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    DataTable dt = new DataTable();
    BindingSource bindingSource = new BindingSource();
    private void Form1_Load(object sender, EventArgs e)
    {
        dt.Columns.Add("DueDate");
        dt.Rows.Add("a");

        bindingSource.DataSource = dt;

        this.textBox1.DataBindings.Add((new Binding("Text", bindingSource, "DueDate", true, DataSourceUpdateMode.OnPropertyChanged)));
    }

    private void button1_Click(object sender, EventArgs e)
    {
        DataRowView drv = bindingSource.Current as DataRowView;
        drv.Row[0] = "new";
    }
}

Best Regards,

---

Bob Wu [MSFT]
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