gridview 清空

 using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

using System.Collections;
using System.Data.OracleClient;

using InforSys.App_Code.Database;

public partial class InterFace_InforCenter_InforIssue : System.Web.UI.Page
{

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {

            dropListInit();

            fillGridView();
        }

    }

    private void dropListInit()
    {
        GetTableInformation getTableInformation = new GetTableInformation();
        // 获取表结构信息
        Hashtable tableInfor = getTableInformation.getTableInfor("xxtable");
        
        tableInfor.Remove("SN");
        
        foreach (DictionaryEntry de in tableInfor)
        {
            String key = de.Key.ToString();
            String value = de.Value.ToString();

            DropDownList9.Items.Add(key);

            switch (value)
            {
                case "CHAR":
                    DropDownList1.Items.Add(key);
                    DropDownList3.Items.Add(key);
                    break;

                case "VARCHAR2":
                    DropDownList1.Items.Add(key);
                    DropDownList3.Items.Add(key);
                    break;

                case "NUMBER":
                    DropDownList5.Items.Add(key);
                    DropDownList7.Items.Add(key);
                    break;
            }

        }

        DropDownList2.Items.Add("包含");
        DropDownList2.Items.Add("不包含");

        DropDownList4.Items.Add("包含");
        DropDownList4.Items.Add("不包含");

        DropDownList6.Items.Add("等于");
        DropDownList6.Items.Add("大于");
        DropDownList6.Items.Add("小于");

        DropDownList8.Items.Add("等于");
        DropDownList8.Items.Add("大于");
        DropDownList8.Items.Add("小于");

    }

    protected void Menu1_MenuItemClick(object sender, MenuEventArgs e)
    {
        if (Menu1.SelectedItem.Text.Equals("信息栏"))
        {
            MultiView1.ActiveViewIndex = 0;
        }
        else if (Menu1.SelectedItem.Text.Equals("详细信息"))
        {
            MultiView1.ActiveViewIndex = 1;
        }
    }

    /// <summary>
    /// 填充GridView
    /// </summary>
    protected void fillGridView()
    {
        DataSet ds = new DataSet();

        ds = GetData();
        // 将ds作为GridView的数据源

        GridView1.DataSource = ds;

        // 绑定数据
        GridView1.DataBind();
 
    }


    /// <summary>
    /// 填充GridView
    /// </summary>
    protected void fillGridView2()
    {
        DataSet ds = new DataSet();

        ds = GetData2();
        // 将ds作为GridView的数据源

        GridView1.DataSource = ds;

        // 绑定数据
        GridView1.DataBind();

    }

    /// <summary>
    /// 转换SQL查询结果为DataSet
    /// </summary>
    /// <returns>ds</returns>
    private DataSet GetData()
    {

        OracleConnection conn = new OracleConnection("Data Source=INFOPLAT;User ID=infomanager;Password=admin;");

        OracleCommand cmd = new OracleCommand();

        cmd.Connection = conn;
        String strSql = "SELECT 建立日期,信息标题,发布部门,经办人,信息类型,信息内容,关键字,阅读次数 FROM xxtable ";

        cmd.CommandText = strSql;

        cmd.CommandType = CommandType.Text;
        // 创建数据集
        DataSet ds = new DataSet();
        try
        {
            conn.Open();

            // 创建适配器
            OracleDataAdapter ad = new OracleDataAdapter();

            // 适配器命令
            ad.SelectCommand = cmd;

            // 填充到数据集(DataSet)

            ad.Fill(ds);

        }
        catch (Exception ex)
        {
            Response.Write("数据库错误，错误原因：" + ex.Message);
            Response.End();
        }
        finally
        {
            // 释放占有资源
            conn.Close();
        }

        return ds;

    }


    /// <summary>
    /// 转换SQL查询结果为DataSet
    /// </summary>
    /// <returns>ds</returns>
    private DataSet GetData2()
    {

        OracleConnection conn = new OracleConnection("Data Source=INFOPLAT;User ID=infomanager;Password=admin;");

        OracleCommand cmd = new OracleCommand();

        cmd.Connection = conn;
        String strSql = "SELECT 建立日期,信息标题,发布部门,经办人,信息类型,信息内容,关键字,阅读次数,SN FROM xxtable where 发布部门='d' ";

        cmd.CommandText = strSql;

        cmd.CommandType = CommandType.Text;
        // 创建数据集
        DataSet ds = new DataSet();
        try
        {
            conn.Open();

            // 创建适配器
            OracleDataAdapter ad = new OracleDataAdapter();

            // 适配器命令
            ad.SelectCommand = cmd;

            // 填充到数据集(DataSet)

            ad.Fill(ds);

        }
        catch (Exception ex)
        {
            Response.Write("数据库错误，错误原因：" + ex.Message);
            Response.End();
        }
        finally
        {
            // 释放占有资源
            conn.Close();
        }

        return ds;

    }

    protected void Button2_Click(object sender, EventArgs e)
    {
        this.TextBox1.Text = "text1";
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        this.TextBox1.Text = "text1";


        GridView1.DataSource = null;

        //GridView1.DataBind();
        fillGridView2();
    }

    protected void Button3_Click(object sender, EventArgs e)
    {
        int cols = 5; 
        String sn = this.GridView1.Rows[this.GridView1.SelectedRow.RowIndex].Cells[5].Text.ToString();
        this.TextBox2.Text = sn;
        
    }
}

这个方法比较全面，下面还有一种方法就是比较简单了：

string str = ConfigurationManager.ConnectionStrings["cnn"].ConnectionString;
        SqlConnection con = new SqlConnection(str);
        con.Open();
        for (int i = 0; i < GridView1.Rows.Count; i++)
        {
            SqlCommand cmd = new SqlCommand("delete from kaoqin where id='" + GridView1.DataKeys[i].Value + "'", con);
            cmd.ExecuteNonQuery();
        }
        this.GridView1.DataSource = null;
        this.DataBind();

希望可以帮住你么解决困难。using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

using System.Collections;
using System.Data.OracleClient;

using InforSys.App_Code.Database;

public partial class InterFace_InforCenter_InforIssue : System.Web.UI.Page
{

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {

            dropListInit();

            fillGridView();
        }

    }

    private void dropListInit()
    {
        GetTableInformation getTableInformation = new GetTableInformation();
        // 获取表结构信息
        Hashtable tableInfor = getTableInformation.getTableInfor("xxtable");
        
        tableInfor.Remove("SN");
        
        foreach (DictionaryEntry de in tableInfor)
        {
            String key = de.Key.ToString();
            String value = de.Value.ToString();

            DropDownList9.Items.Add(key);

            switch (value)
            {
                case "CHAR":
                    DropDownList1.Items.Add(key);
                    DropDownList3.Items.Add(key);
                    break;

                case "VARCHAR2":
                    DropDownList1.Items.Add(key);
                    DropDownList3.Items.Add(key);
                    break;

                case "NUMBER":
                    DropDownList5.Items.Add(key);
                    DropDownList7.Items.Add(key);
                    break;
            }

        }

        DropDownList2.Items.Add("包含");
        DropDownList2.Items.Add("不包含");

        DropDownList4.Items.Add("包含");
        DropDownList4.Items.Add("不包含");

        DropDownList6.Items.Add("等于");
        DropDownList6.Items.Add("大于");
        DropDownList6.Items.Add("小于");

        DropDownList8.Items.Add("等于");
        DropDownList8.Items.Add("大于");
        DropDownList8.Items.Add("小于");

    }

    protected void Menu1_MenuItemClick(object sender, MenuEventArgs e)
    {
        if (Menu1.SelectedItem.Text.Equals("信息栏"))
        {
            MultiView1.ActiveViewIndex = 0;
        }
        else if (Menu1.SelectedItem.Text.Equals("详细信息"))
        {
            MultiView1.ActiveViewIndex = 1;
        }
    }

    /// <summary>
    /// 填充GridView
    /// </summary>
    protected void fillGridView()
    {
        DataSet ds = new DataSet();

        ds = GetData();
        // 将ds作为GridView的数据源

        GridView1.DataSource = ds;

        // 绑定数据
        GridView1.DataBind();
 
    }


    /// <summary>
    /// 填充GridView
    /// </summary>
    protected void fillGridView2()
    {
        DataSet ds = new DataSet();

        ds = GetData2();
        // 将ds作为GridView的数据源

        GridView1.DataSource = ds;

        // 绑定数据
        GridView1.DataBind();

    }

    /// <summary>
    /// 转换SQL查询结果为DataSet
    /// </summary>
    /// <returns>ds</returns>
    private DataSet GetData()
    {

        OracleConnection conn = new OracleConnection("Data Source=INFOPLAT;User ID=infomanager;Password=admin;");

        OracleCommand cmd = new OracleCommand();

        cmd.Connection = conn;
        String strSql = "SELECT 建立日期,信息标题,发布部门,经办人,信息类型,信息内容,关键字,阅读次数 FROM xxtable ";

        cmd.CommandText = strSql;

        cmd.CommandType = CommandType.Text;
        // 创建数据集
        DataSet ds = new DataSet();
        try
        {
            conn.Open();

            // 创建适配器
            OracleDataAdapter ad = new OracleDataAdapter();

            // 适配器命令
            ad.SelectCommand = cmd;

            // 填充到数据集(DataSet)

            ad.Fill(ds);

        }
        catch (Exception ex)
        {
            Response.Write("数据库错误，错误原因：" + ex.Message);
            Response.End();
        }
        finally
        {
            // 释放占有资源
            conn.Close();
        }

        return ds;

    }


    /// <summary>
    /// 转换SQL查询结果为DataSet
    /// </summary>
    /// <returns>ds</returns>
    private DataSet GetData2()
    {

        OracleConnection conn = new OracleConnection("Data Source=INFOPLAT;User ID=infomanager;Password=admin;");

        OracleCommand cmd = new OracleCommand();

        cmd.Connection = conn;
        String strSql = "SELECT 建立日期,信息标题,发布部门,经办人,信息类型,信息内容,关键字,阅读次数,SN FROM xxtable where 发布部门='d' ";

        cmd.CommandText = strSql;

        cmd.CommandType = CommandType.Text;
        // 创建数据集
        DataSet ds = new DataSet();
        try
        {
            conn.Open();

            // 创建适配器
            OracleDataAdapter ad = new OracleDataAdapter();

            // 适配器命令
            ad.SelectCommand = cmd;

            // 填充到数据集(DataSet)

            ad.Fill(ds);

        }
        catch (Exception ex)
        {
            Response.Write("数据库错误，错误原因：" + ex.Message);
            Response.End();
        }
        finally
        {
            // 释放占有资源
            conn.Close();
        }

        return ds;

    }

    protected void Button2_Click(object sender, EventArgs e)
    {
        this.TextBox1.Text = "text1";
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        this.TextBox1.Text = "text1";


        GridView1.DataSource = null;

        //GridView1.DataBind();
        fillGridView2();
    }

    protected void Button3_Click(object sender, EventArgs e)
    {
        int cols = 5; 
        String sn = this.GridView1.Rows[this.GridView1.SelectedRow.RowIndex].Cells[5].Text.ToString();
        this.TextBox2.Text = sn;
        
    }
}

这个方法比较全面，下面还有一种方法就是比较简单了：

string str = ConfigurationManager.ConnectionStrings["cnn"].ConnectionString;
        SqlConnection con = new SqlConnection(str);
        con.Open();
        for (int i = 0; i < GridView1.Rows.Count; i++)
        {
            SqlCommand cmd = new SqlCommand("delete from kaoqin where id='" + GridView1.DataKeys[i].Value + "'", con);
            cmd.ExecuteNonQuery();
        }
        this.GridView1.DataSource = null;
        this.DataBind();

希望可以帮住你么解决困难。