将消息从存储过程返回到C#app

Question

我有一个添加用户的存储过程,并且在我添加的每个权限中,我想开始构建成功消息.

我的存储过程运行正常,但如何将成功消息重新发送回我的应用程序中的消息对话框？

我想在我的C#app中的消息框中显示以下@text.

DECLARE @text NVARCHAR(1000)
SET @text = 'This is line 1.' + CHAR(13)+CHAR(10) + 'This is line 2.'
SELECT @text

这是我在C#应用程序中的调用:

    public DataTable CreateOrDropUser(string dataBase, string procedure, SqlParameter[] parameters)
    {
       try
       {
          if (dataBase.Length > 0) { procedure = dataBase + ".." + procedure; } //Set procedure to DBNAME..ProcedureName

          SqlCommand cmd1 = new SqlCommand(procedure, con);
          cmd1.CommandType = CommandType.StoredProcedure;

          foreach (SqlParameter p in parameters)
          {
              if (p != null)
              {
                  cmd1.Parameters.Add(p);
              }
          }

          con.Open();
          DataTable dt = new DataTable();
          SqlDataAdapter da = new SqlDataAdapter(cmd1);
          da.Fill(dt);
          con.Close();

          MessageBox.Show("Success"); //This should display the @text variable in my proc

          return dt;      
     }
     catch (Exception ex)
     {
        try
        {
           if (con.State == ConnectionState.Open)
           {
              con.Close();
           }
        }
        catch
        {
           MessageBox.Show("Could not connect to database. Check settings. " + ex.Message, "Connection Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }

        MessageBox.Show(ex.Message);
        return null;
      }      
    }

---

我的存储过程,只关注所有打印的部分,这是我正在添加的文本:

ALTER PROCEDURE [dbo].[AdminDevUserCreate]
    @SQLLoginName varchar(50),
    @SQLLoginPass varchar(50) 
AS


DECLARE @text NVARCHAR(1000)OUTPUT  

--PRINT 'Create SQL Login'
SET @text = 'Create SQL Login ' + @SQLLoginName 
-- USE [Master]

EXEC(' USE [master] CREATE LOGIN [' + @SQLLoginName + '] WITH PASSWORD=''' + @SQLLoginPass + ''', DEFAULT_DATABASE=[TestAudit], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF')

--PRINT 'Add Server Roles'
SET @text += + CHAR(13)+CHAR(10) + 'Add Server Roles'
--Add Server roles
    EXEC master..sp_addsrvrolemember @loginame = @SQLLoginName, @rolename = N'bulkadmin'
    EXEC master..sp_addsrvrolemember @loginame = @SQLLoginName, @rolename = N'processadmin'
    EXEC master..sp_addsrvrolemember @loginame = @SQLLoginName, @rolename = N'securityadmin'   
--PRINT 'Allow SQL Agent Job Manage'
SET @text += + CHAR(13)+CHAR(10) + 'Allow SQL Agent Job Manage'
--USE [MSDB]
EXEC ('msdb..sp_addrolemember ''SQLAgentOperatorRole'', ''' + @SQLLoginName + '''')

--PRINT 'Allow Trace'
SET @text += + CHAR(13)+CHAR(10) + 'Allow Trace'
--Allow trace (SQL Profiler)
--USE [MASTER]
EXEC (' USE [MASTER] GRANT ALTER TRACE TO ' + @SQLLoginName )

--PRINT 'Prevent admin proc changes '
SET @text += + CHAR(13)+CHAR(10) + 'Prevent admin proc changes '
    EXEC ('USE [TestAudit] DENY ALTER ON [TestAudit].[dbo].[Admin] TO ' + @SQLLoginName) --Prevents changes to Admin function
--PRINT 'Prevent database trigger changes'
SET @text += + CHAR(13)+CHAR(10) + 'Prevent database trigger changes'
    EXEC ('USE [TestAudit] DENY ALTER ANY DATABASE DDL TRIGGER TO ' + @SQLLoginName) --Prevents modify of [SchemaAuditTrigger]

PRINT @text
Select @text

Answer 1

最好的办法是使用输出参数.

在存储过程中添加参数@text nvarchar(1000) OUTPUT然后在代码中添加带有名称的额外参数@text并将参数方向设置为output.

然后只需SET @text = 'This is line 1.' + CHAR(13)+CHAR(10) + 'This is line 2.'在存储过程中添加该行

编辑:我的回答是,如果您不希望这会影响您当前的查询,如果我误解了您的问题,请告诉我.另外,要获取该值,执行查询后,您可以@name使用.Value 从参数中获取值

编辑2:示例代码应该看起来像

//Add these lines
SqlParameter text = new SqlParameter("@name", SqlDbType.NVarChar);
text.Direction = ParameterDirection.Output;
cmd1.Parameters.Add(text);

con.Open();
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(cmd1);
da.Fill(dt);
con.Close();

//Change this line
MessageBox.Show(text.Value); //This should display the @text variable in my proc

如果您需要有关存储过程的帮助,请发布它,我也会给出一个例子

编辑3:快速示例使用快速示例进行测试.C#代码:

        using (SqlConnection connection = new SqlConnection(@"Data Source=.\SQLExpress;Initial Catalog=TestDB;Integrated Security=True"))
        {
            connection.Open();
            using (SqlCommand command = connection.CreateCommand())
            {
                command.CommandType = CommandType.StoredProcedure;
                command.CommandText = "Test";

                SqlParameter text = new SqlParameter("@Text", SqlDbType.NVarChar, 1000);
                text.Direction = ParameterDirection.Output;
                command.Parameters.Add(text);

                using (DataTable dt = new DataTable())
                {
                    using (SqlDataAdapter da = new SqlDataAdapter(command))
                    {
                        da.Fill(dt);
                    }
                }

                Trace.WriteLine(text.Value);

                connection.Close();
            }
        }

存储过程:

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE PROCEDURE Test
    @Text Nvarchar(1000) OUTPUT
AS
BEGIN
    SET NOCOUNT ON;

    SET @Text = 'test'
END
GO

如果你想与你的差异进行检查,那对我来说工作得很好

编辑4:在您的存储过程中,@ text需要是一个参数,而不是

ALTER PROCEDURE [dbo].[AdminDevUserCreate]
    @SQLLoginName varchar(50),
    @SQLLoginPass varchar(50) 
AS

DECLARE @text NVARCHAR(1000)OUTPUT  

做了

ALTER PROCEDURE [dbo].[AdminDevUserCreate]
    @SQLLoginName varchar(50),
    @SQLLoginPass varchar(50),
    @text NVARCHAR(1000) OUTPUT 
AS

也在创建SqlParameter时使用

SqlParameter text = new SqlParameter("@Text", SqlDbType.NVarChar, 1000);

当你告诉它参数是什么时应该摆脱尺寸问题 NVARCHAR(1000)

这条线

PRINT @text
Select @text

不应该需要