Custom enum poser

[John Smith]

I have a custom enum to list comparison operators: =, <, <=, >, >= . I have
created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum values to/from
the actual comparison operator strings. As I understand it, I can't add
methods to an enum, so is there any more elegant way to do this?

TIA

[Chris R. Timmons]

"John Smith" <JS****@Phoney. com> wrote in
news:e6******** ******@TK2MSFTN GP12.phx.gbl:

I have a custom enum to list comparison operators: =, <, <=, >,

= . I have created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum
values to/from the actual comparison operator strings. As I
understand it, I can't add methods to an enum, so is there any
more elegant way to do this?

John,

One solution would be to use a Hashtable:
using System;
using System.Collecti ons;

namespace Main
{
public class MainClass
{
public enum Comparator
{
Equal,
LessThan,
LessThanOrEqual ,
GreaterThan,
GreaterThanOrEq ual
}

private static Hashtable comparators = new Hashtable();

[STAThread]
public static void Main(string[] args)
{
comparators.Add (Comparator.Equ al, "=");
comparators.Add (Comparator.Les sThan, "<");
comparators.Add (Comparator.Les sThanOrEqual, "<=");
comparators.Add (Comparator.Gre aterThan, ">");
comparators.Add (Comparator.Gre aterThanOrEqual , ">=");
comparators.Add ("=", Comparator.Equa l);
comparators.Add ("<", Comparator.Less Than);
comparators.Add ("<=", Comparator.Less ThanOrEqual);
comparators.Add (">", Comparator.Grea terThan);
comparators.Add (">=", Comparator.Grea terThanOrEqual) ;

Console.WriteLi ne("The Comparator.Less ThanOrEqual sign is {0}",
comparators[Comparator.Less ThanOrEqual].ToString());
Console.WriteLi ne("The name of the Comparator enum for " +
"the > sign is {0}",
Enum.GetName(ty peof(Comparator ), (int) comparators[">"]));
}
}
}

Hope this helps.

Chris.
-------------
C.R. Timmons Consulting, Inc.
http://www.crtimmonsinc.com/

[Nicole Calinoiu]

Create a class that contains both the enum and a method (probably static) to
map an particular value to the operator string. The enum could, of course,
be separate from the class that contains the method, but the encapsulation
wouldn't be quite as clean.

HTH,
Nicole
"John Smith" <JS****@Phoney. com> wrote in message
news:e6******** ******@TK2MSFTN GP12.phx.gbl...

I have a custom enum to list comparison operators: =, <, <=, >, >= . I have created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum values to/from
the actual comparison operator strings. As I understand it, I can't add
methods to an enum, so is there any more elegant way to do this?

TIA

[Bret Mulvey]

A very .NET-ish sort of way would be to use attributes. First, create an
attribute class that can be used to assign a string label to something, such
as an enum value. This is more code than you need for your specific case,
but this is a very general class that can be used to assign a string label
to pretty much anything, for any purpose. Very reusable.
using System;

[AttributeUsage( AttributeTarget s.All)]
public class LabelAttribute : Attribute
{
public readonly string Label;

public LabelAttribute( string label)
{
Label = label;
}

public static string FromMember(obje ct o)
{
return ((LabelAttribut e)
o.GetType().Get Member(o.ToStri ng())[0].GetCustomAttri butes(typeof(La belAttri
bute), false)[0]).Label;
}

public static string FromType(object o)
{
return ((LabelAttribut e)
o.GetType().Get CustomAttribute s(typeof(LabelA ttribute), false)[0]).Label;
}
}
Then you can use this attribute class to associate a string label with each
of your enum values:
[Label("Comparis on operators")]
public enum Comparator
{
[Label("=")]
Equal,

[Label("<")]
LessThan,

[Label("<=")]
LessThanOrEqual ,

[Label(">")]
GreaterThan,

[Label(">=")]
GreaterThanOrEq ual,
}
And this is how you would read those labels:
Comparator x = Comparator.Grea terThanOrEqual;
string valueLabel = LabelAttribute. FromMember(x);
string typeLabel = LabelAttribute. FromType(x);


"John Smith" <JS****@Phoney. com> wrote in message
news:e6******** ******@TK2MSFTN GP12.phx.gbl...

I have a custom enum to list comparison operators: =, <, <=, >, >= . I have created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum values to/from
the actual comparison operator strings. As I understand it, I can't add
methods to an enum, so is there any more elegant way to do this?

TIA

[Bret Mulvey]

A very .NET-ish sort of way would be to use attributes. First, create an
attribute class that can be used to assign a string label to something, such
as an enum value. This is more code than you need for your specific case,
but this is a very general class that can be used to assign a string label
to pretty much anything, for any purpose. Very reusable.
using System;

[AttributeUsage( AttributeTarget s.All)]
public class LabelAttribute : Attribute
{
public readonly string Label;

public LabelAttribute( string label)
{
Label = label;
}

public static string FromMember(obje ct o)
{
return ((LabelAttribut e)
o.GetType().Get Member(o.ToStri ng())[0].GetCustomAttri butes(typeof(La belAttri
bute), false)[0]).Label;
}

public static string FromType(object o)
{
return ((LabelAttribut e)
o.GetType().Get CustomAttribute s(typeof(LabelA ttribute), false)[0]).Label;
}
}
Then you can use this attribute class to associate a string label with each
of your enum values:
[Label("Comparis on operators")]
public enum Comparator
{
[Label("=")]
Equal,

[Label("<")]
LessThan,

[Label("<=")]
LessThanOrEqual ,

[Label(">")]
GreaterThan,

[Label(">=")]
GreaterThanOrEq ual,
}
And this is how you would read those labels:
Comparator x = Comparator.Grea terThanOrEqual;
string valueLabel = LabelAttribute. FromMember(x);
string typeLabel = LabelAttribute. FromType(x);


"John Smith" <JS****@Phoney. com> wrote in message
news:e6******** ******@TK2MSFTN GP12.phx.gbl...

I have a custom enum to list comparison operators: =, <, <=, >, >= . I have created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum values to/from
the actual comparison operator strings. As I understand it, I can't add
methods to an enum, so is there any more elegant way to do this?

TIA

[John Smith]

You get the prize, Bret! Thanks to Nicole and Chris too, for their excellent
suggestions.

"Bret Mulvey" <br***@microsof t.nospam0000.co m> wrote in message
news:hf******** ************@rw crnsc51.ops.asp .att.net...

A very .NET-ish sort of way would be to use attributes. First, create an
attribute class that can be used to assign a string label to something, such as an enum value. This is more code than you need for your specific case,
but this is a very general class that can be used to assign a string label
to pretty much anything, for any purpose. Very reusable.
using System;

[AttributeUsage( AttributeTarget s.All)]
public class LabelAttribute : Attribute
{
public readonly string Label;

public LabelAttribute( string label)
{
Label = label;
}

public static string FromMember(obje ct o)
{
return ((LabelAttribut e)
o.GetType().Get Member(o.ToStri ng())[0].GetCustomAttri butes(typeof(La belAttri bute), false)[0]).Label;
}

public static string FromType(object o)
{
return ((LabelAttribut e)
o.GetType().Get CustomAttribute s(typeof(LabelA ttribute), false)[0]).Label;
}
}
Then you can use this attribute class to associate a string label with each of your enum values:
[Label("Comparis on operators")]
public enum Comparator
{
[Label("=")]
Equal,

[Label("<")]
LessThan,

[Label("<=")]
LessThanOrEqual ,

[Label(">")]
GreaterThan,

[Label(">=")]
GreaterThanOrEq ual,
}
And this is how you would read those labels:
Comparator x = Comparator.Grea terThanOrEqual;
string valueLabel = LabelAttribute. FromMember(x);
string typeLabel = LabelAttribute. FromType(x);


"John Smith" <JS****@Phoney. com> wrote in message
news:e6******** ******@TK2MSFTN GP12.phx.gbl...

I have a custom enum to list comparison operators: =, <, <=, >, >= . I

have

created it as follows:

public enum Comparator {Equal, LessThan,
LessThanOrEqual ,GreaterThan,Gr eaterThanOrEqua l}

Now I have to create static functions to convert these enum values to/from the actual comparison operator strings. As I understand it, I can't add
methods to an enum, so is there any more elegant way to do this?

TIA