怎么清空dataGridView

Question

以下是我的代码：
public partial class FrmWareList : Form
    {
        private DataSet dataSet = new DataSet();
        private SqlDataAdapter dataAdapter;
        string Sql;
        public FrmWareList()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            lb();
            tj();
        }
        private void lb()
        {
            Sql = "SELECT WareNO,WareName,UnitPrice,WareId FROM Wares";
            if(comboBox1.SelectedIndex == 0 || comboBox1.SelectedIndex == -1)
            {
            }
            else if (comboBox1.SelectedIndex == 1)
            {
                Sql = "SELECT WareNO,WareName,UnitPrice,WareId FROM Wares Where CategoryId like '1' ";
            }
            else
            {
                Sql = "SELECT WareNO,WareName,UnitPrice,WareId FROM Wares Where CategoryId like '2' ";
            }
            dataAdapter = new SqlDataAdapter(Sql, DB.connection);
            dataAdapter.Fill(dataSet, "Wares");
            dataGridView1.DataSource = dataSet.Tables["Wares"];
           
        }
        private void tj() 
        {            Sql = "SELECT CatagoryName FROM WareManagement";
            SqlCommand command = new SqlCommand(Sql, DB.connection);
            try
            {
                DB.connection.Open();
                SqlDataReader dataReader = command.ExecuteReader();
                string lx = "";
                while (dataReader.Read())
                {
                    lx = (string)dataReader[0];
                    comboBox1.Items.Add(lx);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally 
            {
                DB.connection.Close();
            }
        }
        private void button1_Click(object sender, EventArgs e)
        {
            DialogResult result = MessageBox.Show("确实要将修改保存到数据库中吗？", "操作提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Question);
            if (result == DialogResult.OK)
            {
                SqlCommandBuilder builder = new SqlCommandBuilder(dataAdapter);
                dataAdapter.Update(dataSet, "Wares");
            }
        }        private void button2_Click(object sender, EventArgs e)
        {
            lb();
        }
    }
                                                                                                      谢谢了！

Answer 1

设置一个null DataSource，
一个空List都可以吧

Answer 2

谢谢你们可以了，
private void button2_Click(object sender, EventArgs e)
            {
                dataSet.Clear();
                lb();
            }
在那里加了之后就解决了，谢谢！

Answer 3

设置数据源为空就可以了。this.dataGridView1.DataSource = null;

Answer 4

DataTable dt = (DataTable)datagradeview.DataSource;
           dt.Rows.Clear();
           datagradeview.DataSource = dt;
给它重新绑定个datatable，
这样不会因为清空数据源而把列也清除掉了。