Search results
26 cze 2023 · You can write a Generic function to check Null and include default value when it is NULL. Call this when reading Datareader public T CheckNull<T>(object obj) { return (obj == DBNull.Value ? default(T) : (T)obj); }
21 mar 2012 · You can use DBNull.Value when you need to pass NULL as a parameter to the stored procedure. param.Value = DBNull.Value; Or you can use that instead of your if operator: param.Value = !string.IsNullOrEmpty(activity.StaffId) ? activity.StaffId : (object)DBNull.Value;
The IsNull function for each SqlType returns a SqlBoolean and can be used to check for null values. The following truth tables show how the AND, OR, and NOT operators function in the presence of a null value. (T=true, F=false, and U=unknown, or null.)
9 sty 2021 · You can check if the column is null by comparing it with DBNull.Value or by using SqlDataReader.IsDBNull(). Here’s an example showing these two ways of checking if a column is null:
10 paź 2016 · The most terse and declarative way to write this is to use C#'s ?? operator. Your line becomes: new SqlParameter("@Price", (object)items.Price ?? DbNull.Value), The expression here will either return the non-null value of the left operand (items.Price), or return the operand to the right instead.
7 sie 2024 · When passing nullable values to SQL queries using SQLParameter, it's important to handle null values appropriately to prevent SQL injection vulnerabilities and ensure the correct behavior of the query. Here's an example of how you can handle a nullable parameter in C# using SQLParameter: int? nullableValue = null;
28 sty 2021 · SQL databases operate on 3-valued logic (true, false, null) when performing comparisons, as opposed to the boolean logic of C#. When translating LINQ queries to SQL, EF Core tries to compensate for the difference by introducing additional null checks for some elements of the query.
