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copied!<p>The original code had several fundamental errors. This demonstrates how to do it <em>right</em>, including how to set DBNull:</p> <pre><code>[HttpPost] public void UpdateTitle(Title title) { string query; if (title.Operation == 'U') { query = "UPDATE dbo.AWD_Titles" + " SET AwardStatusId = @AwardStatusID , Description = @Description , IsVerified= @IsVerified , EpisodeAKA= @EpisodeAKA" + " WHERE AwardTitleId= @AwardTitleId ;" + " SELECT SCOPE_IDENTITY();"; } else { query=""; //presumably you have a slightly different query string for inserts. //Thankfully, they should have pretty much the same set of parameters. //If this method will really only be called for updates, the code is quite a bit simpler } //instead of a shared myConnection object, use a shared connection string. // .Net is set up so that you should be creating a new connection object for most queries. // I know it sounds backwards, but that's really the right way to do it. // Create the connection in a using(){} block, so that you guarantee it is // disposed correctly, even if an exception is thrown. using (var cn = new SqlConnection(myConnectionString)) using (var cmd = new SqlCommand(query, cn)) { //guessing at database types, lengths here. Fix with actual column types cmd.Parameters.Add("@AwardStatusId", SqlDbType.Int).Value = title.AwardStatus; cmd.Parameters.Add("@Description", SqlDbType.NVarChar, 250).Value = title.Description; cmd.Parameters.Add("@IsVerified", SqlDbType.Bit).Value = title.IsVerified; cmd.Parameters.Add("@EpisodeAKA", SqlDbType.NVarChar, 100).Value = title.EpisodeAKA; cmd.Parameters.Add("@AwardTitleId", SqlDbType.Int).Value = title.AwardTitleId; //------------- //This is the part that actually answers your question foreach (var p in cmd.Parameters.Where(p => p.Value == null)) { p.Value = DBNull.Value; } //------------- cn.Open(); cmd.ExecuteScalar(); } } </code></pre>

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