返回行数并赋值给Int变量的查询

Question

我正在选择我的查询中的行数。我需要将它赋给一个int变量。我该如何做到这一点呢？

Display.aspx.cs

            **int TotalYesVotes;**
            Ratings GetYesVotes = new Ratings();
            DataTable DATotalYesVotes = GetYesVotes.GetTotalYesVotes();
            **//How do i assign that count to TotalYesVotes**

业务层

     public DataTable GetTotalYesVotes()
     {

         DLRatings DlTotalyesVotes = new DLRatings();
         return DlTotalyesVotes.GetTotalYesVotes();

     }

我的数据层

    public DataTable GetTotalNoVotes()
    {
        //get database connection string from config file
        string strConectionString o= ConfigurationManager.AppSettings["DataBaseConnection"];

        //set up sql
        string StrSql = "SELECT COUNT(*) AS Expr1 FROM Ratings WHERE (PicRating = 2) AND (PicID = 2)";

        DataTable dt = new DataTable();
        using (SqlDataAdapter daObj = new SqlDataAdapter(StrSql, strConectionString))
        {

            //fill data table
            daObj.Fill(dt);
        }
        return dt;
        }

Answer 1

你应该在数据检索方面做很多改变：

   public int GetTotalNoVotes()
    {
        //get database connection string from config file
        string strConectionString o= ConfigurationManager.AppSettings["DataBaseConnection"];

        SqlConnection conn = new SqlConnection(strConnectionString);
        conn.Open();

        SqlCommand oCommand = new SqlCommand("SELECT COUNT(1) AS Expr1 FROM Ratings WHERE (PicRating = 2) AND (PicID = 2)", conn);

        object oValue = oCommand.ExecuteScalar();

        conn.Close();

        if (oValue == DBNull.Value) {
           return 0;
        } else {
          return Convert.ToInt32(oValue);
        }
   }