c# - 如何用SQL Table填充DataTable

Question

我目前正在使用 Page_Load 中的以下代码创建和读取数据表

protected void Page_Load(object sender, EventArgs e)
{
    if (Session["AllFeatures1"] == null)
    {
        Session["AllFeatures1"] = GetData();
    }
    table = (DataTable)Session["AllFeatures1"];
    DayPilotCalendar1.DataSource = Session["AllFeatures1"];
    DayPilotNavigator1.DataSource = Session["AllFeatures1"];

    if (!IsPostBack)
    {
        DataBind();
        DayPilotCalendar1.UpdateWithMessage("Welcome!");
    }

    if (User.Identity.Name != "")
    {
        Panel1.Visible = true;
    }
}

我想知道如何转换这段代码以便它从 SQL 查询中读取？我正在试验下面的代码，但我不确定如何连接它们，以便我的页面加载中的数据表填充下面的 SQL 命令。

SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["BarManConnectionString"].ConnectionString);
conn.Open();
string query = "SELECT * FROM [EventOne]";

SqlCommand cmd = new SqlCommand(query, conn);

DataTable t1 = new DataTable();
using (SqlDataAdapter a = new SqlDataAdapter(cmd))
{
    a.Fill(t1);
}

我被困在:

table = (DataTable)Session["AllFeatures1"]; 

我希望它是 t1 = (DataTable)Session["AllFeatures1];

Answer 1

SqlDataReader 是DataTable 的有效数据源。因此，您需要做的就是:

public DataTable GetData()
{
    SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["BarManConnectionString"].ConnectionString);
    conn.Open();
    string query = "SELECT * FROM [EventOne]";
    SqlCommand cmd = new SqlCommand(query, conn);

    DataTable dt = new DataTable();
    dt.Load(cmd.ExecuteReader());
    conn.Close();
    return dt;
}