How to check if an object is an Enum

Question

I have a SQL query builder method:

public static string PreprocessSQL(string sql, params object[] args)

Provided that the sql parameter is "String.Format friendly", this method loops through the params and plugs them into the query string, doing whatever needs to be done based on the type of the argument - convert a null to string "NULL", surround a string with single quotes, etc.

Now the problem is with enums. I need a logic that checks if the type of current args[i] is Enum, and if so, convert it to int. How to do this check? My first guess, for some reason, doesn't work:

if(args[i].GetType() == typeof(Enum)) {
    converted.Add((int)args[i]);
}

The above condition apparently gets evaluated as false.

My enum class is:

public enum Priority {
    Low,
    Normal,
    High
}

If a pass a value of Priorty.Normal to this method, I figured the "value" is Normal, and the type of that value is Priority, which autmatically inherits from Enum, so I'm done. Turns out it's not that simple, and from what I can tell, it looks like the type of the value Normal is actually Priority.Normal

Now I could explicitly check for all the enums I'm using in my project, it's only 2 classes actually, but would that even work?

if(args[i].GetType() == typeof(Priority)) { ... }

I mean, if type of args[i] is Priority.Normal, this would too evaluate as false.

How do I check an unknown object o has the type of a enumeration class?

possible duplicate of [Getting Type of Enum witnin class through C# reflection](http://stackoverflow.com/questions/9408800/getting-type-of-enum-witnin-class-through-c-sharp-reflection) — SQLMason, Nov 19 '13 at 12:14
http://social.msdn.microsoft.com/Forums/vstudio/en-US/a78445ca-c004-4612-938b-0a70734f817e/enum-gettype?forum=csharpgeneral — SQLMason, Nov 19 '13 at 12:16

Sriram Sakthivel · Accepted Answer · 2013-11-19T12:20:03.543

3

You can check IsEnum property.

args[i].GetType().IsEnum

Or

if(args[i] is Enum)
{
}

Or

bool isEnum = typeof(Enum).IsAssignableFrom(args[i].GetType());

Or

bool isEnum = typeof(Enum).IsInstanceOfType(o);

edited Nov 19 '13 at 12:20

answered Nov 19 '13 at 12:14

Sriram Sakthivel

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@DanAndrews And I think you're pointing to java. In .Net we use `is` keyword for the same thing. Correct me if am wrong – Sriram Sakthivel Nov 19 '13 at 12:23
You're right, I'm still sleeping. That's the problem with being a code monkey. – SQLMason Nov 19 '13 at 12:24

score 1 · Answer 2 · answered Nov 19 '13 at 12:14

1

Try this

 bool isEnum = o is Enum;

answered Nov 19 '13 at 12:14

Microsoft DN

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score 0 · Answer 3 · answered Nov 19 '13 at 12:15

0

You can leverage the IsEnum property of System.Type

bool isEnum = typeof(YourType).IsEnum

answered Nov 19 '13 at 12:15

Moo-Juice

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How to check if an object is an Enum

3 Answers3