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Inline IF Statement in C#

How will I write an Inline IF Statement in my C# Service class when setting my enum value according to what the database returned?

For example: When the database value returned is 1 then set the enum value to VariablePeriods, when 2 then FixedPeriods.

Hope you can help.

The literal answer is:

return (value == 1 ? Periods.VariablePeriods : Periods.FixedPeriods);

Note that the inline if statement, just like an if statement, only checks for true or false. If (value == 1) evaluates to false, it might not necessarily mean that value == 2. Therefore it would be safer like this:

return (value == 1
    ? Periods.VariablePeriods
    : (value == 2
        ? Periods.FixedPeriods
        : Periods.Unknown));

If you add more values an inline if will become unreadable and a switch would be preferred:

switch (value)
{
case 1:
    return Periods.VariablePeriods;
case 2:
    return Periods.FixedPeriods;
}

The good thing about enums is that they have a value, so you can use the values for the mapping, as user854301 suggested. This way you can prevent unnecessary branches thus making the code more readable and extensible.

You may define your enum like so and use cast where needed

public enum MyEnum
{
    VariablePeriods = 1,
    FixedPeriods = 2
}

Usage

public class Entity
{
    public MyEnum Property { get; set; }
}

var returnedFromDB = 1;
var entity = new Entity();
entity.Property = (MyEnum)returnedFromDB;

You can do inline ifs with

return y == 20 ? 1 : 2;

which will give you 1 if true and 2 if false.

This is what you need : ternary operator, please take a look at this

http://msdn.microsoft.com/en-us/library/ty67wk28%28v=vs.80%29.aspx

http://www.dotnetperls.com/ternary

Enum to int: (int)Enum.FixedPeriods

Int to Enum: (Enum)myInt

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