c# - 无法提供存储过程参数

Question

OpenSqlConnection();

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

SqlDataReader dr = cmd.ExecuteReader();

当我运行上面的代码时，它会抛出异常

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

但是正如您在代码中看到的那样，我正在提供 @CharacterID 参数，它不是空的或 null。

存储过程:

    [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

有什么建议吗？

Answer 1

我会尝试明确指定参数的类型 - 如果值为 null 则尤为重要:

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;

还有:你有没有错别字？？ 三次检查所有出现的CharacterID - 你的代码中是否碰巧有CharachterID或类似的东西？？