c# - 在 C# ASP.Net 中查找当前星期几

Question

我想在 c# ASP.Net 中找到当前星期几:

System.DateTime.Now.DayOfWeek.ToString(); 

此代码在控制台应用程序中运行良好，但当我尝试将此行的值存储在 ASP.Net 网站中的字符串中时，它没有返回任何内容。

有人能帮忙吗？

StringBuilder message = null;

protected void Page_Load(object sender, EventArgs e)
{
    var dayofweek = System.DateTime.Now.DayOfWeek.ToString();
    String conn = "Data Source=.;Initial Catalog=OCSI;Integrated Security=True";//conne
    SqlConnection sqlconne = new SqlConnection(conn);

    string selectSQL = "SELECT lec FROM schedule WHERE [day]='" + dayofweek +"'";
    SqlCommand cmd = new SqlCommand(selectSQL, sqlconne);
    SqlDataReader reader = null;
    try
    {
        sqlconne.Open();
        reader = cmd.ExecuteReader();
        message = new StringBuider(); 
        while (reader.Read())
        {
            message.Append(reader["lec"].ToString());
           //question what are you using message for ...?
            Label3.Text = dayofweek;
        }
        reader.Close();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Mesage);
    }
    finally
    {
        sqlconne.Close();
        // you neeed to Dispose of all other objects here too
        // StringBuilder Object
        // SqlDataReader Object
        //SqlCommand  Object.. 
        //Look into wrapping your Connection / Command Sql Dataobject around a using() {}
    }

我想在 where 子句 SQL 查询中使用当天从数据库表中获取与当天相关的数据。

我用var作为

 protected void Page_Load(object sender, EventArgs e)
 {
    String conn = "Data Source=.;Initial Catalog=OCSI;Integrated Security=True";//conne
    SqlConnection sqlconne = new SqlConnection(conn);

    var testDay = DateTime.Now.DayOfWeek.ToString();

    // string selectSQL = "SELECT lec FROM schedule WHERE [day]='" + dayofweek +"'";
    string selectSQL = string.Format("SELECT lec FROM schedule WHERE [day]= {0}", testDay);
    SqlCommand cmd = new SqlCommand(selectSQL, sqlconne);
    SqlDataReader reader;
    try
    {
        sqlconne.Open();
        reader = cmd.ExecuteReader();

        while (reader.Read())
        {
            message += reader["lec"].ToString();

            Label3.Text = testDay;
        }
        reader.Close();
    }
    catch
    { 
    }
    finally
    {
        sqlconne.Close();
    }

Answer 1

它对我来说很好。