Run stored procedure in C#, pass parameters and capture the output result

Question

This is a simple task that I want to acheive but ASP.NET makes it quite difficult, next to impossible. I followed this question Running a Stored Procedure in C# Button but found out ExecuteNonQuery does not return the output from query.

I tried this other approach but can't seem to pass the paremeters in this way

SqlConnection myConnection = new SqlConnection(myconnectionString);

SqlCommand myCommand = new SqlCommand();
myCommand.CommandType = CommandType.StoredProcedure;
myCommand.CommandText = "usp_GetCustomer";

myCommand.SelectParameter <-- does not exist

Can someone write this simple code, how can I implement it? Basically I am passing a @username and @month (both character strings) to stored procedure and it returns a number that I want to capture and assign to a label control.

Thank you

The output from my query is this. It runs a complex query, create a temp table and then it runs

select @@rowcount

and I am capturing that.

Solution 1

1. Don't use SqlCommand.ExecuteNonQuery() if you actually want data from a result set.

2. Make sure your procedure uses set nocount on

3. Then use SqlCommand.ExecuteScalar()

   return (int)myCommand.ExecuteScalar(); // value of select @@rowcount
   

Edit: As for your parameters:

myCommand.Parameters.AddWithValue("@username","jsmith");
myCommand.Parameters.AddWithValue("@month","January");

Solution 2

I prefer using linq-to-sql to handle stored procedures. Create a linq-to-sql model, where you add the SP you want to call. This will expose the SP as a function on the generated data context, where the parameters are ordinary C# functions. The returned values will be exposed as a collection of C# objects.

If you have multiple results from the SP things get a bit more complicated, but still quite straight forward.

Solution 3

Use the Parameters collection of the command to set the parameters, and the ExecuteScalar to run the query and get the value from the single-row single-column result.

Use using blocks to make sure that the connection and command are closed and disposed properly in any situation. Note that you have to provide the connection to the command object:

int result;
using (SqlConnection connection = new SqlConnection(myconnectionString)) {
  using (SqlCommand command = new SqlCommand(connection)) {
    command.CommandType = CommandType.StoredProcedure;
    command.CommandText = "usp_GetCustomer";
    command.Parameters.Add("@username", SqlDbType.VarChar).Value = username;
    command.Parameters.Add("@month", SqlDbType.VarChar).Value = month;
    connection.Open();
    result = (int)myCommand.ExecuteScalar();
  }
}

Comments

[Hammad Khan]

this will apply to this code stackoverflow.com/questions/4124100/… ?

[canon]

Updated to include parameter info.

[Guffa]

The value is returned as a result, not a return value. Also, you need to provide the connection to command for that code to work.

[Hammad Khan]

so it is working upto this point but now I need to change a parameter value and call ExecuteScalar again. The new parameter name is @Type. Can you help?

[canon]

Alternatively, you could leave nocount off, omit the select @@rowcount and use the return value of ExecuteNonQuery for your rowcount.

[Osman Villi]

Not correct this line: "DbType.VarChar". This must be "SqlDbType.VarChar"

[Guffa]

The value is returned as a result, not a return value.

[Guffa]

The value is returned as a result, not a return value.