~楓花雪岳~: [C#] DataGridView 刪除資料

星期五, 8月 05, 2016

[C#] DataGridView 刪除資料

紀錄在 DataGridView 內刪除資料的兩種方法

FullRowSelect 狀態下且啟用刪除，按 Delete 鍵
透過 ContextMenuStrip 來進行刪除

Project

Layout

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            dataGridView1.AutoGenerateColumns = false;
            dataGridView1.AllowUserToAddRows = false;
            dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill;
            dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;

            dataGridView1.Columns.Add(new DataGridViewTextBoxColumn
            {
                DataPropertyName = "ID",
                Name = "ColID",
                HeaderText = "流水號",
                Width = 100,
                Visible = true,
                SortMode = DataGridViewColumnSortMode.Automatic
            });

            dataGridView1.Columns.Add(new DataGridViewTextBoxColumn
            {
                DataPropertyName = "ProdName",
                Name = "ColProdName",
                HeaderText = "產品名稱",
                Width = 100,
                Visible = true,
                SortMode = DataGridViewColumnSortMode.Automatic
            });

            dataGridView1.DataSource = GetDataSource();
            dataGridView1.MouseDown += DataGridView1_MouseDown;
            dataGridView1.UserDeletingRow += DataGridView1_UserDeletingRow;
        }

        private void DataGridView1_UserDeletingRow(object sender, DataGridViewRowCancelEventArgs e)
        {
            DialogResult result =
                MessageBox.Show(
                    "是否刪除該筆資料",
                    "確認",
                    MessageBoxButtons.YesNo,
                    MessageBoxIcon.Question);

            if (result == DialogResult.No) e.Cancel = true;
        }

        private void DataGridView1_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button != MouseButtons.Right) return;

            DataGridView dgv = sender as DataGridView;
            ShowMenu(dgv, e);
        }

        private void ShowMenu(DataGridView dgv, MouseEventArgs args)
        {

            // 取得 RowIndex 
            // 方法 1：透過 HitTest()
            int RowIndex = dgv.HitTest(args.X, args.Y).RowIndex;
            // 方法 2：CurrentRow
            int RowIndex = dgv.CurrentRow.Index;
            if (RowIndex < 0) return;

            ContextMenuStrip menu = new ContextMenuStrip();
            ToolStripMenuItem item = new ToolStripMenuItem("删除該筆資料");
            item.Click += (sender, e) =>
            {
                dgv.Rows.RemoveAt(RowIndex);
            };
            menu.Items.Add(item);

            // 四種指定 ContextMenuStrip 位置方式
            // 方法 1
            menu.Show(dgv, new Point(e.X, e.Y));
            // 方法 2
            menu.Show(dgv, e.Location);
            // 方法 3
            menu.Show(Cursor.Position);
            // 方法 4：DataGridView 也有 PointToClient() 可以使用
            menu.Show(dgv, dgv.PointToClient(Cursor.Position));
        }

        private DataTable GetDataSource()
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("ID", typeof(int));
            dt.Columns.Add("ProdName", typeof(string));
            dt.Rows.Add(1, "SQL Server 2016");
            dt.Rows.Add(2, "SQL Server 2014");
            dt.Rows.Add(3, "SQL Server 2012");
            dt.Rows.Add(4, "SQL Server 2008");
            dt.Rows.Add(5, "SQL Server 2005");
            return dt;
        }
    }
}

利用 ContextMenuStrip 刪除資料