How to pass a null variable to a SQL Stored Procedure from C#.net code
C#SqlSql ServerStored ProceduresC# Problem Overview
Im calling a SQL stored procedure from a piece of C#.net code:
SqlHelper.ExecuteDataset(sqlConnection, CommandType.StoredProcedure, STORED_PROC_NAME, sqlParameters);
where the sqlParameters
variable is defined as:
SqlParameter[] sqlParameters = new SqlParameter[SQL_NUMBER_PARAMETERS];
Log.Logger.Debug(string.Format("Running proc: {0} ", STORED_PROC_NAME));
SqlParameters[0] = new SqlParameter("fieldID", SqlDbType.BigInt );
SqlParameters[0].Value = fieldID;
SqlParameters[0].Direction = ParameterDirection.Input;
I need to now pass in another two parameters to this Stored Proc, (both are of type SqlDateTime
), which are going to NULL in this case.
Thanks,
IN
C# Solutions
Solution 1 - C#
SqlParameters[1] = new SqlParameter("Date1", SqlDbType.SqlDateTime);
SqlParameters[1].Value = DBNull.Value;
SqlParameters[1].Direction = ParameterDirection.Input;
...then copy for the second.
Solution 2 - C#
Use DBNull.Value
Better still, make your stored procedure parameters have defaults of NULL. Or use a Nullable<DateTime>
parameter if the parameter will sometimes be a valid DateTime object
Solution 3 - C#
You can pass the DBNull.Value
into the parameter's .Value property:
SqlParameters[0] = new SqlParameter("LedgerID", SqlDbType.BigInt );
SqlParameters[0].Value = DBNull.Value;
Just adjust for your two DateTime parameters, obviously - just showing how to use the DBNull.Value
property value here.
Marc
Solution 4 - C#
Old question, but here's a fairly clean way to create a nullable parameter:
new SqlParameter("@note", (object) request.Body ?? DBNull.Value);
If request.Body has a value, then it's value is used. If it's null, then DbNull.Value is used.
Solution 5 - C#
I use a method to convert to DBNull if it is null
// Converts to DBNull, if Null
public static object ToDBNull(object value)
{
if (null != value)
return value;
return DBNull.Value;
}
So when setting the parameter, just call the function
sqlComm.Parameters.Add(new SqlParameter("@NoteNo", LibraryHelper.ToDBNull(NoteNo)));
This will ensure any nulls, get changed to DBNull.Value, else it will stay the same.
Solution 6 - C#
try this! syntax less lines and even more compact! don't forget to add the properties you want to add with this approach!
cmd.Parameters.Add(new SqlParameter{SqlValue=(object)username??DBNull.Value,ParameterName="user" } );
Solution 7 - C#
SQLParam = cmd.Parameters.Add("@RetailerID", SqlDbType.Int, 4)
If p_RetailerID.Length = 0 Or p_RetailerID = "0" Then
SQLParam.Value = DBNull.Value
Else
SQLParam.Value = p_RetailerID
End If
Solution 8 - C#
Let's say the name of the parameter is "Id" in your SQL stored procedure, and the C# function you're using to call the database stored procedure is name of type int?
. Given that, following might solve your issue :
public void storedProcedureName(Nullable<int> id, string name)
{
var idParameter = id.HasValue ?
new SqlParameter("Id", id) :
new SqlParameter { ParameterName = "Id", SqlDbType = SqlDbType.Int, Value = DBNull.Value };
// to be continued...