Question

这是我的搜索功能与gridview.I＆＃39;我无法在表单中获得gridview仍然很好。我在这里添加了新的第二列。请帮助我。谢谢

private void txtSearch02()
    {
        DataTable dt = new DataTable();
        SqlConnection con = new SqlConnection(myStr);
        SqlCommand cmd = new SqlCommand("select ItemCode,ItemName,PointsNeeded from tb_ItemRedemption where (ItemCode is null or ItemCode='" + txtkey2.Text.Trim() + "') or (ItemName is null or ItemName='" + txtkey2.Text.Trim() + "')", con);
        SqlDataAdapter sda = new SqlDataAdapter(cmd);
        Session["ItemCode"] = dt;
        con.Open();
        DataSet ds = new DataSet();
        sda.Fill(ds);
        dt = ds.Tables[0];
        con.Close();
        dt.Columns.Add("Quantity");
        dt.Columns.Add("TotalPoints");

        // for caliculation 
        txtPointsNeeded.Text = dt.Rows[0]["PointsNeeded"].ToString();
        //dt.Rows[0]["Quantity"].ToString();
        //dt.Rows[0]["TotalPoints"].ToString();
        DataRow dr;
        dr = dt.NewRow();
        dt.Rows.Add(dr);
        // for caliculation 
        txtGetQuantity.Text = txtQuantity.Text;
        GridView1.DataSource = dt;
       GridView1.DataBind();
        GridView1.Visible = true;


    }

Answer 1

如果你有前三列（带有bindvalue）并添加其他两列，那么它会让人感到困惑。再次将所有列添加到datatable。意味着三个和两个新的。

试试吧。它应该工作。因为你的代码是正确的。

Answer 2

确保您的自动生成列设置为“true”。

转到网格视图的属性，如果为false，则将自动生成的列更改为true。

浏览链接以进一步说明：Click here

Answer 3

继续我关于参数化查询和使用'using（）{}'语句的评论后，我首先写下这样的内容：

DataTable dt = new DataTable();

using (SqlConnection con = new SqlConnection(myStr))
{
    string sql = "select ItemCode,ItemName,PointsNeeded from tb_ItemRedemption where (ItemCode is null or ItemCode = @txtkey2) or (ItemName is null or ItemName = @txtkey2)";

    SqlCommand cmd = new SqlCommand(sql, con);
    cmd.Parameters.Add("@txtkey2", txtkey2.Text.Trim());

    SqlDataAdapter sda = new SqlDataAdapter(cmd);
    //You're currently adding a blank DataTable to a session variable below as you've not 
    //filled it yet. I've left this incase that's what you meant to do.
    Session["ItemCode"] = dt;

    con.Open();

    //SqlDataAdapter should be able to fill a DataTable as well as a dataset.
    sda.Fill(dt);

    if (dt.Rows.Count > 0) //Put a breakpoint here to check if anything is returned in dt
    {
        dt.Columns.Add("Quantity");
        dt.Columns.Add("TotalPoints");

        // for caliculation 
        txtPointsNeeded.Text = dt.Rows[0]["PointsNeeded"].ToString();

        //Not sure what you're trying to do here. You're just adding a blank row to dt.
        DataRow dr;
        dr = dt.NewRow();
        dt.Rows.Add(dr);

        // for caliculation 
        txtGetQuantity.Text = txtQuantity.Text;

        GridView1.DataSource = dt;
        GridView1.DataBind();
        GridView1.Visible = true;
    }
    else
    {
        //Code to handle nothing being returned.
    }
}

添加新列时无法获取GRIDVIEW

3 个答案: