Question

OpenSqlConnection();

SqlCommand cmd = new SqlCommand("ReturnCharacterInfo", Con);
cmd.Parameters.AddWithValue("@CharacterID", CharacterID);

SqlDataReader dr = cmd.ExecuteReader();

When I run code you can see above, it throws exception

Procedure or function ‘ReturnCharacterInfo’ expects parameter ‘@CharacterID’, which was not supplied.

but as you can see at the code, I’m suppying @CharacterID parameter and it’s not empty or null.

Stored procedure:

    [ReturnCharacterInfo] @CharacterID int 
as
   select 
      CharacterName, characterSurname, CharacterIsMale, CharacterAge, 
      CharacterMood, CharacterHealth, CharacterInCity, CharacterInLocation, 
      Cities.CityName, Locales.LocaleTitle 
   from 
      Characters 
   INNER JOIN 
      Cities on Cities.CityID = Characters.CharacterInCity
   INNER JOIN 
      Locales on Locales.LocaleID = Characters.CharacterInLocation
   Where 
      CharacterID = @CharacterID

Any suggestions?

Answer 1

I would try to explicitly specifying the type of the parameter – especially important if the value is null:

SqlCommand cmd = new SqlCommand("ReturnCharacterInfo", Con);

// added as per CodeNaked's comment - thanks! You've nailed it right on the head!
cmd.CommandType = CommandType.StoredProcedure;

cmd.Parameters.Add("@CharacterID", SqlDbType.Int).Value = CharacterID;

Also: do you have a typo anywhere?? Triple-check all occurrences of CharacterID – do you happen to have CharachterID or something like that somewhere in your code??