AddParameter new SqlParameter " column", object x?? Value ; would give you a parm with a value of DBNull. Value ; Would give you a parm with "A String" as the value. Improve this answer. Walden Leverich Walden Leverich 4, 2 2 gold badges 20 20 silver badges 30 30 bronze badges.
The compiler will choke on this because it can't implicitly convert from string to DBNull. You are correct. You need to downcast the string x to an object.
Edited example. Not a fan of this, because it makes it easy for. Net to guess the wrong type for a parameter. It would be better to specify the parameter type via an overload that asks for an SqlDbType enum.
You can use the?? AddParameter new SqlParameter " column", myNull?? Value ;?? Edit Fixed the code above so it will compile you need to cast DBNull. Value to an object. JoshBerke JoshBerke I believe you can use testString?? How about object testString?? Vale — recursive. Maybe the ternary operator is something you find usefull. In expressions using arithmetic operators, if any of the operands is null, the result is null as well.
Comparison between any System. SqlTypes will return a SqlBoolean. However, you can't prevent different connections from setting null options for that connection. Null values are special, and their storage and assignment semantics differ across different type systems and storage systems.
A Dataset is designed to be used with different type and storage systems. This section describes the null semantics for assigning null values to a DataColumn in a DataRow across the different type systems. Value This assignment is valid for a DataColumn of any type. Value is coerced into the appropriate strongly typed Null value. Null All System. SqlTypes data types implement INullable. If the strongly typed null value can be converted into the column's data type using implicit cast operators, the assignment should go through.
Otherwise an invalid cast exception is thrown. In this case, if a strongly typed null value associated with the derived class is assigned, it is stored as an untyped DbNull. Value , because null storage is always consistent with the DataColumn's data type. Add , DataTable. If an object in the array contains DbNull. If all expressions are non-nullable, the result is typed as non-nullable.
Returns the data type of expression with the highest data type precedence. Thanks for reading. Next Recommended Reading. Net Core 6. Create A. However, the old "accepted answer" that uses cast with object?? Value works correctly. The ADO. I suggest that others carefully test Brian's tip to make sure null behavior is working as expected. This answer only replaces an explicit cast to object with an implicit. In the sample code, exampleNoCast is declared object, so the cast to object still occurs.
If, like in the OP's code, the value is assigned directly to SqlParameter. Value which is also of type object, then you still get the cast. AgeIndex; As follows: if AgeItem. Value; else planIndexParameter. AgeIndex; Because you can't use different type of values in conditional statement, as DBNull and int are different from each other. Leandro Bardelli 8, 13 13 gold badges 66 66 silver badges bronze badges. ShahidAzim ShahidAzim 1, 1 1 gold badge 9 9 silver badges 15 15 bronze badges.
This answer is really nice because it examples in every way possible. I like the first approach, I usually use EF but in this requirement could not do it and it saves me a lot of time. Value ;. Adrian Adrian 6, 5 5 gold badges 26 26 silver badges 26 26 bronze badges.
You can also cast AgeItem. AgeIndex to an object: object AgeItem. But yea also prefer your approach — Jordec. So you could fix it by casting one of both to System. Object : planIndexParameter. Value : object AgeItem. GetUnderlyingType t! Equals default T , val ; else if t. Tim Schmelter Tim Schmelter k 64 64 gold badges silver badges bronze badges.
But if the value is DBNull. Value , ADO. Try this: if AgeItem. Flipster Flipster 4, 4 4 gold badges 27 27 silver badges 35 35 bronze badges. But now, you're just omitting a parameter - I highly doubt the stored procedure will be happy about this Happens all the time.
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