ExecutenonQuery不工作

Question

我已经存储了proc，如下：

ALTER PROC pr_Update_Users_Nomination
(
      @UserID AS VARCHAR(100),  
      @Nominated AS BIT
)
AS

UPDATE User
SET isNominated = @Nominated
WHERE 
EMPID = @UserID;

我想从c#代码中调用此过程:以下是我正在尝试的代码：

void OpenConnection()
{
string Nominated = "False";
    //Connection String
        string sConnString = System.Configuration.ConfigurationManager.ConnectionStrings["ConString1"].ConnectionString;
        SqlConnection mySqlCon = new SqlConnection(sConnString);
        SqlCommand mySqlCom = mySqlCon.CreateCommand();

        //Call the stored proc and provide in parameters
        mySqlCom.CommandText = "EXECUTE pr_Update @UserID @Nominated";
        mySqlCom.Parameters.Add("@UserID", SqlDbType.VarChar, 20).Value = UserID;
        mySqlCom.Parameters.Add("@Nominated", SqlDbType.Bit).Value = Nominated;

        mySqlCon.Open();
        mySqlCom.ExecuteNonQuery();
        mySqlCon.Close();
}

我收到一个错误，说

Incorrect Syntax near @Nominated

Answer 1

首先，在执行带有参数的过程时，请用逗号分隔参数

EXECUTE pr_Update @UserID, @Nominated

其次，将您的代码修改为：

    string sConnString = System.Configuration.ConfigurationManager.ConnectionStrings["ConString1"].ConnectionString;
    using(SqlConnection mySqlCon = new SqlConnection(sConnString))
    {
        using(SqlCommand mySqlCom = new SqlCommand())
        {
            mySqlCom.Connection = mySqlCon;
            mySqlCom.CommandText = "pr_Update";
            mySqlCom.CommandType = CommandType.StoredProcedure;
            mySqlCom.Parameters.Add("@UserID", SqlDbType.VarChar, 20).Value = UserID;
            mySqlCom.Parameters.Add("@Nominated", SqlDbType.Bit).Value = Nominated;
            try
            {
                mySqlCon.Open();
                mySqlCom.ExecuteNonQuery();
            }
            catch(SqlException ex)
            {
                // do something with the exception
                // don't hide it
            }

        }
    }

Answer 2

参数之间缺少逗号(，)。

它应该是

mySqlCom.CommandText = "EXECUTE pr_Update @UserID, @Nominated";
mySqlCom.Parameters.Add("@UserID", SqlDbType.VarChar, 20).Value = UserID;
mySqlCom.Parameters.Add("@Nominated", SqlDbType.Bit).Value = Nominated;

或者，由于您所做的只是调用一个存储的proc，因此您可以执行以下操作：

mySqlCom.CommandType = CommandType.StoredProcedure ;
mySqlCom.CommandText = "pr_Update"; //no need to specify parameter names
mySqlCom.Parameters.Add("@UserID", SqlDbType.VarChar, 20).Value = UserID;
mySqlCom.Parameters.Add("@Nominated", SqlDbType.Bit).Value = Nominated;

Answer 3

仅提供存储过程的名称，因为您将在此之后的语句中添加参数。还要设置CommandType。

 mySqlCom.CommandText = "pr_Update";
 mySqlCom.CommandType = CommandType.StoredProcedure;