sql server - Using stored procedure output parameters in C# -

i having problem returning output parameter sql server stored procedure c# variable. have read other posts concerning this, not here on other sites, , cannot work. here have. trying print value comes back. following code returns null value. trying return primary key. have tried using @@identity , scope_indentity() (i.e. set @newid = scope_identity()).

stored procedure:

create procedure usp_insertcontract     @contractnumber varchar(7),      @newid int output begin      insert [dbo].[contracts] (contractnumber)         values (@contractnumber)      select @newid = id [dbo].[contracts] contractnumber = @contractnumber end 

opening database:

pvconnectionstring = "server = desktop-pc\\sqlexpress; database = pvdatabase; user id = sa;     password = *******; trusted_connection = true;";  try {     pvconnection = new sqlconnection(pvconnectionstring);     pvconnection.open(); } catch (exception e) {     databaseerror = true; } 

executing command:

pvcommand = new sqlcommand("usp_insertcontract", pvconnection);  pvcommand.transaction = pvtransaction; pvcommand.commandtype = commandtype.storedprocedure;      pvcommand.parameters.clear(); pvcommand.parameters.add(new sqlparameter("@contractnumber", contractnumber));  sqlparameter pvnewid = new sqlparameter(); pvnewid.parametername = "@newid"; pvnewid.dbtype = dbtype.int32; pvnewid.direction = parameterdirection.output; pvcommand.parameters.add(pvnewid);  try {     sqlrows = pvcommand.executenonquery();      if (sqlrows > 0)         debug.print("new id inserted =  ",              pvcommand.parameters["@newid"].value.tostring());      }     catch (exception e)     {         debug.print("insert exception type: {0}", e.gettype());         debug.print("  message: {0}", e.message);     } } 

i modified stored procedure (to use scope_identity) , looks this:

create procedure usp_insertcontract     @contractnumber varchar(7),     @newid int output begin     insert [dbo].[contracts] (contractnumber)     values (@contractnumber)      select @newid = scope_identity() end 

i tried , works fine (with modified stored procedure):

// define connection , command, in using blocks ensure disposal using(sqlconnection conn = new sqlconnection(pvconnectionstring )) using(sqlcommand cmd = new sqlcommand("dbo.usp_insertcontract", conn)) {     cmd.commandtype = commandtype.storedprocedure;      // set parameters     cmd.parameters.add("@contractnumber", sqldbtype.varchar, 7);     cmd.parameters.add("@newid", sqldbtype.int).direction = parameterdirection.output;      // set parameter values     cmd.parameters["@contractnumber"].value = contractnumber;      // open connection , execute stored procedure     conn.open();     cmd.executenonquery();      // read output value @newid     int contractid = convert.toint32(cmd.parameters["@newid"].value);     conn.close(); } 

does work in environment, too? can't why original code won't work - when here, vs2010 , sql server 2008 r2, works flawlessly....

if don't value - suspect table contracts might not have column identity property on it.