DataTable似乎丢失了数据

当我想向datatable中添加列时,是否过度编写了datatable?我知道,如果我在FinishButton()事件中写入输出窗口,结果就在那里,但当我在pushdatatosql()方法中写入输出时,结果是空的。我将Datatable定义为类变量。

我在这里错误地编码了什么?

DataTable dtResult = new DataTable();

protected void FinishBtn_Click(object sender, EventArgs e)
{
    pushdatatosql();
}

protected void Wizard1_FinishButtonClick(object sender, WizardNavigationEventArgs e)
{
    DataRow dr = null;
    dtResult.Columns.Add(new DataColumn("mainevent", typeof(string)));
    dtResult.Columns.Add(new DataColumn("secondevent", typeof(string)));

    foreach (GridViewRow gr in grdOther.Rows)
    {
        dr = dtResult.NewRow();
        TextBox box1 = (TextBox)gr.Cells[1].FindControl("txtmainevent");
        TextBox box2 = (TextBox)gr.Cells[2].FindControl("txtse");

        dr["mainevent"] = box1.Text;
        dr["secondevent"] = box2.Text;

        dtResult.Rows.Add(dr);
    }
}


protected void pushdatatosql()
{
    foreach (DataRow dataRow in dtResult.Rows)
    {
        foreach (var item in dataRow.ItemArray)
        {
            System.Diagnostics.Debug.WriteLine(item);
        }
    }

    using (SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["SQLString"].ConnectionString))
    {
        connection.Open();
        using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection))
        {
            foreach (DataColumn c in dtResult.Columns)
                bulkCopy.ColumnMappings.Add(c.ColumnName, c.ColumnName);

            bulkCopy.DestinationTableName = "TestInsertTable";
                bulkCopy.WriteToServer(dtResult);
        }
    }
}