如何根据组合框选择更新datagridview？

Question

I am attempting to write code that will display data in a datagridview based off of the size of car selected in a combo box. When this code initially runs, it defaults to economy sized, and displays the correct information in the datagridview. However, when a different size is selected in the combo box, the text boxes update correctly while the datagridview remains the same. What can I do to make it update every time the combo box is changed? I thought the code in "private void cboSize_selectionChangeCommitted()" would accomplish this, but there was no change in the output.

namespace carForm
{
    public partial class Form1 : Form
    {
        _Cars_1_DataSet cDataSet;
        BindingSource sizeBindingSource;
        BindingSource vehicleBindingSource;
        CarsDataClass clsCarsData;

        Boolean gridInitialized;

        public Form1()
        {
            InitializeComponent();
        }

        private void exitToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // TODO: This line of code loads data into the '_Cars_1_DataSet.Reservations' table. You can move, or remove it, as needed.
            this.reservationsTableAdapter.Fill(this._Cars_1_DataSet.Reservations);
            // TODO: This line of code loads data into the '_Cars_1_DataSet.Vehicle' table. You can move, or remove it, as needed.
            this.vehicleTableAdapter.Fill(this._Cars_1_DataSet.Vehicle);
            // TODO: This line of code loads data into the '_Cars_1_DataSet.CarSize' table. You can move, or remove it, as needed.
            this.carSizeTableAdapter.Fill(this._Cars_1_DataSet.CarSize);
            clsCarsData = new CarsDataClass();
            cDataSet = clsCarsData.GetDataSet();

            //Binding source sizes
            sizeBindingSource = new BindingSource();
            sizeBindingSource.DataSource = cDataSet;
            sizeBindingSource.DataMember = "CarSize";

            //Binding source vehicles
            vehicleBindingSource = new BindingSource();
            vehicleBindingSource.DataSource = cDataSet;
            vehicleBindingSource.DataMember = "Vehicle";

            //Combo box
            cboSize.DataSource = sizeBindingSource;
            cboSize.DisplayMember = "Size";
            cboSize.ValueMember = "SizeCode";

            //bind other controls
            txtDaily.DataBindings.Add("text", sizeBindingSource, "DailyRate");
            txtMileage.DataBindings.Add("text", sizeBindingSource, "MileageRate");

            //execute combo box
            cboSize_SelectionChangeCommitted(cboSize, e);
        }

        private void cboSize_SelectionChangeCommitted(object sender, EventArgs e)
        {
            string carSelected;
            carSelected = Convert.ToString(cboSize.SelectedValue);
            if (!gridInitialized)
            {
                dgvVehicles.DataSource = vehicleBindingSource;
                gridInitialized = true;
                ChangeGridColumns();
            }
            vehicleBindingSource.Filter = "CarSize = '" + carSelected + "'";
        }

        private void ChangeGridColumns()
        {
            //Change column headers
            //dgvVehicles.Columns["Inv_ID"].Visible = false;
        }
    }
}

Answer 1

使用SelectedIndexChanged而不是SelectionChangeCommitted。

Answer 2

Try using SelectedIndexChanged event from the events menu after clicking on the combobox in the design view.

This should populate in your code:

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
   Console.WriteLine("test!");
}

In there you can put this logic from your code:

string carSelected;
carSelected = Convert.ToString(cboSize.SelectedValue);
if (!gridInitialized)
 {
      dgvVehicles.DataSource = vehicleBindingSource;
      gridInitialized = true;
      ChangeGridColumns();
 }
 vehicleBindingSource.Filter = "CarSize = '" + carSelected + "'";