将多个控件绑定到 ASP.Net WebForm 中的同一数据源

Question

如何将多个控件绑定到同一个数据源？

我通过存储过程调用从 table 获取数据，并希望所有控件都绑定到该数据。

下拉列表绑定成功，其他的绑定失败。为了让它工作，我必须为每个控件创建一个单独的函数并调用存储过程和绑定。

    private void BindServerControls()
    {
        string strErrorMessage = "";

        SqlDataReader LanguagesDataReader = null;

        try
        {
            dbFunc.OpenDB();

            SqlCommand LanguagesCmd = new SqlCommand("dbo.SelectAllLanguages", dbFunc.objConn);
            LanguagesCmd.Parameters.Clear();
            LanguagesCmd.CommandType = CommandType.StoredProcedure;

            LanguagesDataReader = LanguagesCmd.ExecuteReader();

            if (LanguagesDataReader.HasRows == true)
            {
                // Bind a dropdownlist.
                DropDownList1.DataSource = LanguagesDataReader;
                DropDownList1.DataTextField = "ProgrammingLanguage";
                DropDownList1.DataValueField = "ID";
                DropDownList1.DataBind();
                DropDownList1.Items.Insert(0, "Choose...");

                // Bind a list of Radio buttons.
                RadioButtonList1.DataSource = LanguagesDataReader;
                RadioButtonList1.DataTextField = "ProgrammingLanguage";
                RadioButtonList1.DataValueField = "ID";
                RadioButtonList1.DataBind();

                // Bind a ListBox.
                ListBox1.DataSource = LanguagesDataReader;
                ListBox1.DataTextField = "ProgrammingLanguage";
                ListBox1.DataValueField = "ID";
                ListBox1.DataBind();

                // Bind a CheckBoxList.
                CheckBoxList1.DataSource = LanguagesDataReader;
                CheckBoxList1.DataTextField = "ProgrammingLanguage";
                CheckBoxList1.DataValueField = "ID";
                CheckBoxList1.DataBind();

                // Bind a BulletList.
                BulletedList1.DataSource = LanguagesDataReader;
                BulletedList1.DataTextField = "ProgrammingLanguage";
                BulletedList1.DataValueField = "ID";
                BulletedList1.DataBind();
            }
            else
            {
                Status.Text = "There are currently no entries in the 
                database.";
            }
        }
        catch (Exception ex)
        {
            Status.Text = "Unable to get the entries from the database.";
        }
        finally
        {
            if (LanguagesDataReader != null)
            {
                LanguagesDataReader.Close();
            }

            dbFunc.CloseDB();
        }
    }

Answer 1

不是绑定 dataReader 对象，而是在 DataTable 中加载数据，然后使用它进行绑定

DataTable dtLanguages = new DataTable();
using(SqlDataReader LanguagesDataReader = LanguagesCmd.ExecuteReader()) {
  dtLanguages.Load(LanguagesDataReader);
}

if(dtLanguages.Rows.Count > 0) {
// Bind a dropdownlist.
                DropDownList1.DataSource = dtLanguages;
                DropDownList1.DataTextField = "ProgrammingLanguage";
                DropDownList1.DataValueField = "ID";
                DropDownList1.DataBind();
                DropDownList1.Items.Insert(0, "Choose...");
 }

原因是 DataReader 是顺序的、只向前连接的数据源，一旦你通过它完成数据遍历，你就不能返回开始并再次读取。

将多个控件绑定到 ASP.Net WebForm 中的同一数据源

Binding multiple controls to the same datasource in a ASP.Net WebForm

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