DataGridView全部删除不成功？

[bulls5988]

现在button3的dataGridView1.Rows.Clear();删除全部记录,现在
不成功，提示 "不能清除此列表。" 请教是什么原因？

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;


namespace cj_sys
{
    public partial class Form4 : Form
    {
        public Form4()
        {
            InitializeComponent();
        }
        string conn_str = "Server=WIN_TEST;Database=choujiang;uid=sa;pwd=dsd_dsdn";
        string sql_str = "select cj_names as 品牌名称,cj_show_counts as 可抽奖数,cj_old_counts as 原抽奖数,cj_pic_path as 商标路径,cj_date as 加入时间 from cj_main where cj_flag=0 order by cj_date desc"; 
        private SqlDataAdapter find_do;
        private DataSet ds;

        private void Form4_Load(object sender, EventArgs e)
        {
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            this.WindowState = FormWindowState.Maximized;
            SqlConnection conn = new SqlConnection(conn_str);
            SqlCommand cmd = new SqlCommand(sql_str,conn);
            find_do = new SqlDataAdapter();

            find_do.SelectCommand = cmd;

            ds = new DataSet();
            find_do.Fill(ds,"rs");
            dataGridView1.DataSource =ds.Tables["rs"];
            dataGridView1.Columns[0].FillWeight = 50;
            dataGridView1.Columns[1].FillWeight = 50;
            dataGridView1.Columns[2].FillWeight = 50;
            dataGridView1.Columns[3].FillWeight = 260;
            dataGridView1.Columns[4].FillWeight = 70;
            dataGridView1.Columns[2].ReadOnly = true;
            dataGridView1.Columns[4].ReadOnly = true;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            SqlCommandBuilder updates = new SqlCommandBuilder(find_do);
            find_do.UpdateCommand = updates.GetUpdateCommand();
            find_do.Update(ds,"rs");
            dataGridView1.Update();  
        }

        private void button2_Click(object sender, EventArgs e)
        {
            SqlCommandBuilder delete = new SqlCommandBuilder(find_do);
            find_do.DeleteCommand = delete.GetDeleteCommand();
            dataGridView1.Rows.Remove(dataGridView1.CurrentRow);
            find_do.Update(ds, "rs");
            dataGridView1.Update();  
        }

        private void button3_Click(object sender, EventArgs e)
        {
            SqlCommandBuilder delete = new SqlCommandBuilder(find_do);
            find_do.DeleteCommand = delete.GetDeleteCommand();
            dataGridView1.Rows.Clear();
            find_do.Update(ds, "rs");
            dataGridView1.Update();  
        }

       
    }
}

[YangYun]

我也遇到过这个问题，用clear()方法不能清除掉，我最后的解决办法是将与之关联的Datasource，比如DataTable中删除所有datarow后就可以了。

我认为是不是这样的，如果datagridview有了绑定的datasource后，使用clear()就不行，如果直接在items里进行赋值的话，这个时候clear()就可以了，具体是不是这样，还没有进行验证。

[bulls5988]

用foreach遍历删除所有行？

[bulls5988]

SqlCommandBuilder delete = new SqlCommandBuilder(find_do);
            find_do.DeleteCommand = delete.GetDeleteCommand();
            dataGridView.Datasource=null;
            dataGridView1.Rows.Clear();
            find_do.Update(ds, "rs");
            dataGridView1.Update();  

这样虽然清除了，页面上的DataGridView但是数据库中的记录还在。

[bulls5988]

没人知道么?

[josxhn]

你是清空DGV里的内容还是要删除对应数据库的数据

[bulls5988]

当然是要清空数据库这个表中所有的数据了

[josxhn]

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace test_DeleteTableThroughDataGridView
{
	public partial class Form1 : Form
	{
		public SqlDataAdapter da;
		public SqlConnection conn;
		public SqlCommand cmd;
		public SqlCommandBuilder cb;
		public DataSet ds;

		public string CmdText_Select = "select * from [test_2]";

		public Form1()
		{
			InitializeComponent();
			conn = new SqlConnection("Data Source=LX-WORK;Initial Catalog=testdb;Integrated Security=True");
			cmd = new SqlCommand();
			cb = new SqlCommandBuilder();
			da = new SqlDataAdapter();
			ds = new DataSet();
		}

		private void Form1_Load(object sender , EventArgs e)
		{
		}

		//delete data in [test_2] while remove each rows in dataGridView
		private void btn_ClearTable_Click(object sender , EventArgs e)
		{
			conn.Open();
			cb.DataAdapter = da;
			cb.GetDeleteCommand();

			if (dataGridView1.Rows.Count > 0)
				foreach (DataGridViewRow dr in dataGridView1.Rows)
					//look at here please dataGridView1.Rows.Remove(dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex]);

			da.Update(ds.Tables[0]);
			conn.Close();
		}

		//show data
		private void btn_Show_Click(object sender , EventArgs e)
		{
			dataGridView1.DataSource = null;
			conn.Open();
			cmd.CommandText = CmdText_Select;
			cmd.Connection = conn;
			da.SelectCommand = cmd;
			da.Fill(ds , "tb1");
			dataGridView1.DataSource = ds.Tables[0];
			conn.Close();
		}

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

[josxhn]

上面没发好，主要是这里了
也许你已经搞定了

//delete data in [test_2] while remove each rows in dataGridView
private void btn_ClearTable_Click(object sender , EventArgs e)
{
	conn.Open();
	cb.DataAdapter = da;
	cb.GetDeleteCommand();

	if (dataGridView1.Rows.Count > 0)
		foreach (DataGridViewRow dr in dataGridView1.Rows)
			//look at here please
			dataGridView1.Rows.Remove(dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex]);

	da.Update(ds.Tables[0]);
	conn.Close();
}