C#調用SQL中的存儲過程中有output參數，存儲過程執行過程中返回信息

 

C#調用SQL中的存儲過程中有output參數，類型是字符型的時候一定要指定參數的長度。不然獲取到的結果總是只有第一字符。本人就是由於這個原因，折騰了很久。在此記錄一下，供大家以后參考！

例如：

CREATE PROCEDURE sp_AccountRole_Create
@CategoryID int,
@RoleName nvarchar(10),
@Description nvarchar(50),
@RoleID int output
AS
DECLARE @Count int
-- 查找是否有相同名稱的記錄
SELECT @Count = Count(RoleID) FROM Account_Role WHERE
RoleName = @RoleName
IF @Count = 0
INSERT INTO Account_Role 
(CategoryID, RoleName, Description) valueS
(@CategoryID, @RoleName, @Description)
SET @RoleID = @@IDENTITY
RETURN 1
GO

 

SqlConnection DbConnection = new SqlConnection(mConnectionString);
SqlCommand command = new SqlCommand( "sp_AccountRole_Create", DbConnection );
DbConnection.Open(connectString);
// 廢置SqlCommand的屬性為存儲過程
command.CommandType = CommandType.StoredProcedure;
command.Parameters.Add("@CategoryID", SqlDbType.Int, 4);
command.Parameters.Add("@RoleName", SqlDbType.NVarChar, 10);
command.Parameters.Add("@Description", SqlDbType.NVarChar, 50);
command.Parameters.Add("@RoleID", SqlDbType.Int, 4);
// 返回值
command.Parameters.Add("Returnvalue",
SqlDbType.Int,
4, // Size
ParameterDirection.Returnvalue,
false, // is nullable 
0, // byte precision
0, // byte scale
string.Empty,
DataRowVersion.Default,
null );
command.parameters["@CategoryID"].value = permission.CategoryID;
command.parameters["@RoleName"].value = permission.PermissionName;
command.parameters["@Description"].value = permission.Description;
// 可以返回新的ID值
command.parameters["@RoleID"].Direction = ParameterDirection.Output;
int rowsAffected = command.ExecuteNonQuery();
int result = command.parameters["Returnvalue"].value;
int newID = command.parameters["@RoleID"].value;