How to Call a SQL User-Defined Function (UDF) from C#?

Calling a SQL User-Defined Function (UDF) in C#

You want to interact with a SQL scalar function from your C# code, and the following C# code was provided:

public void TotalCupom(int cupom)
{ 
    float SAIDA;           
    SqlDataAdapter da2 = new SqlDataAdapter();

    if (conex1.State == ConnectionState.Closed)
    { 
        conex1.Open();
    }

    SqlCommand Totalf = new SqlCommand("Tcupom", conex1);
    SqlParameter code1 = new SqlParameter("@code", SqlDbType.Int);
    code1.Value = cupom ;
    Totalf.CommandType = CommandType.StoredProcedure ;
    SAIDA = Totalf.ExecuteScalar();

    return SAIDA;
}

However, you're encountering an error. The reason for this is that, unlike stored procedures, you cannot directly call a UDF in SQL from C#.

Solution:

To invoke a UDF in C#, you need to use an inline SQL statement. Here's the adjusted code:

public void TotalCupom(int cupom)
{ 
    float SAIDA;           
    SqlDataAdapter da2 = new SqlDataAdapter();

    if (conex1.State == ConnectionState.Closed)
    { 
        conex1.Open();
    }

    // Use an inline SQL statement with the UDF
    SqlCommand Totalf = new SqlCommand("SELECT dbo.Tcupom(@code)", conex1);

    SqlParameter code1 = new SqlParameter("@code", SqlDbType.Int);
    code1.Value = cupom;

    SAIDA = Totalf.ExecuteScalar();

    return SAIDA;
}

In this modified code, a new inline SQL statement is employed:

SqlCommand Totalf = new SqlCommand("SELECT dbo.Tcupom(@code)", conex1);

This statement references the UDF by its fully qualified name (dbo.Tcupom) and includes a parameter for the @code input value. By using this approach, you can call the Tcupom UDF and retrieve the result in your C# code.

The above is the detailed content of How to Call a SQL User-Defined Function (UDF) from C#?. For more information, please follow other related articles on the PHP Chinese website!