StrataFrame Forum » StrataFrame Application Framework - V1 » Business Objects and Data Access (How do I?) » Accessing EnumDisplayValue programmatically

Accessing EnumDisplayValue programmatically

Leonard P. — Wed, 20 Aug 2008 09:08:48 GMT

Hello,

Lets seay I have this enum type:

[codesnippet]

public enum MyEnum
    {
        [EnumDisplayValue("This is Value 1")]
        value1 = 1,
        [EnumDisplayValue("This is Value 2")]
        value2 = 2
    }

[/codesnippet]

Now consider this code:

[codesnippet]

MyEnum myEnum = MyEnum.value2;
MessageBox.Show(myEnum.ToString());

[/codesnippet]

The messagebox displays "value2", but I would like to see EnumDisplayValue "This is Value 2".

Is there an easy way to get the value of that attribute? I have a feeling I need to use reflections to get it.

Thank you for your help.

RE: Accessing EnumDisplayValue programmatically

Dustin Taylor — Wed, 20 Aug 2008 09:08:48 GMT

Honestly Trent, catch up :D.

RE: Accessing EnumDisplayValue programmatically

Trent L. Taylor — Wed, 20 Aug 2008 09:02:43 GMT

LOL...I just saw that Dustin already mentioned it :D

RE: Accessing EnumDisplayValue programmatically

Trent L. Taylor — Wed, 20 Aug 2008 09:00:07 GMT

You could do all of that to get the EnumDisplayValue or...

[codesnippet]MyEnum myEnum = MyEnum.value2;
MessageBox.Show(MicroFour.StrataFrame.Tools.Common.GetEnumDisplayValue(myEnum)); [/codesnippet]

The framework already has a mechanism for you to do this...and it reduces the code by a lot! ;)

RE: Accessing EnumDisplayValue programmatically

Edhy Rijo — Tue, 19 Aug 2008 23:02:19 GMT

[quote][b]Dustin Taylor (08/19/2008)[/b][hr]Good solutions! :D

For future reference, there is also a built-in function in StrataFrame to do this very thing. MicroFour.StrataFrame.Tools.Common.GetEnumDisplayValue(yourEnum).[/quote]

Hi Dustin,

In this very same topic, today I just hit an Enum Display problem in a Dialog Browser in which the enum is not properly displayed when selected in field for the browser result set as in this picture:

I guess the SF combobox is using the MicroFour.StrataFrame.Tools.Common.GetEnumDisplayValue(EnumValue) but the field in the browser result is not. I fixed my code by changing my DB class and populate the CustomerType field throug the RowPopulating event which works nice, but I wonder if the framework should use the GetEnumDisplayValue() every where an enum is used.

Here is my BD code:

[quote]

Public Class CustomerBrowserDialog

Private Sub CustomerBrowserDialog_RowPopulating(ByVal e As MicroFour.StrataFrame.UI.Windows.Forms.RowPopulatingEventArgs) Handles MyBase.RowPopulating

'-- Strong type the passed business object

With CType(e.BusinessObject, atr_crm.Business.bizCustomers)

'-- Format the customer type enum to display properly.

e.Values(4).DisplayValue = MicroFour.StrataFrame.Tools.Common.GetEnumDisplayValue(.CustomerType)

End With

End Sub

End Class

[/quote]

BTW, thanks to Greg and Leonard, this post came up just on time with my situation, even though I used Dustin approach :D.

RE: Accessing EnumDisplayValue programmatically

Greg McGuffey — Tue, 19 Aug 2008 22:25:28 GMT

Now he tells us.... :P

RE: Accessing EnumDisplayValue programmatically

Dustin Taylor — Tue, 19 Aug 2008 21:33:29 GMT

Good solutions! :D

For future reference, there is also a built-in function in StrataFrame to do this very thing. MicroFour.StrataFrame.Tools.Common.GetEnumDisplayValue(yourEnum).

RE: Accessing EnumDisplayValue programmatically

Greg McGuffey — Tue, 19 Aug 2008 18:28:23 GMT

Ooh, I like the generics....think I'll update my code to use it! Thanks back at ya! :w00t:

RE: Accessing EnumDisplayValue programmatically

Leonard P. — Tue, 19 Aug 2008 13:27:45 GMT

Thanks Greg!

This is pretty much what I did at first (only with Generic method and looping through fields and attributes using reflections) :

[codesnippet]

private static string GetDisplayValueType<T>(Enum customEnum) where T : struct
{

            string retValue = string.Empty;

            foreach (FieldInfo field in typeof(T).GetFields(BindingFlags.Static | BindingFlags.GetField | BindingFlags.Public))
            {

object value = field.GetValue(null);

foreach (Attribute attrib in field.GetCustomAttributes(true))
{

if (attrib is EnumDisplayValueAttribute)
{

                        EnumDisplayValueAttribute customAttr = (EnumDisplayValueAttribute)attrib;
                        if (customEnum.Equals(value))
                        {
                            retValue = customAttr.ValueOrKey;
                            break;
                        }
                    }

}

return retValue;

}

[/codesnippet]

Using your code, I was able to get rid of loops:

[codesnippet]

private static string GetDisplayValueType1<T>(Enum customEnum) where T : struct
{

            string desc = string.Empty;
            FieldInfo field = typeof(T).GetField(Enum.GetName(typeof(T), customEnum));
            EnumDisplayValueAttribute descrAttr = (EnumDisplayValueAttribute)Attribute.GetCustomAttribute(field, typeof(EnumDisplayValueAttribute));
            if (descrAttr != null)
              desc = descrAttr.ValueOrKey;
            else
               desc = customEnum.ToString();

return desc;

}

[/codesnippet]

The second function looks much cleaner :) Thanks!

RE: Accessing EnumDisplayValue programmatically

Greg McGuffey — Tue, 19 Aug 2008 12:50:29 GMT

Leonard,

This is what I use:

[codesnippet] ''' <summary>
''' Give an enum type and a value, return the display text for
''' that value. This will use the EnumDisplayValueAttribute if
''' the enum has one defined.
''' </summary>
''' <param name="enumType">type of enum</param>
''' <param name="value">value to lookup</param>
Public Shared Function GetEnumDisplayText(ByVal enumType As Type, ByVal value As Object) As String
  '-- Establish a return variable
  Dim desc As String = String.Empty

  Dim fi As FieldInfo = enumType.GetField(System.Enum.GetName(enumType, value))
  Dim descAttr As EnumDisplayValueAttribute = DirectCast(Attribute.GetCustomAttribute(fi, GetType(EnumDisplayValueAttribute)), EnumDisplayValueAttribute)
  If descAttr IsNot Nothing Then
    desc = descAttr.GetDisplayValue()
  Else
    desc = value.ToString()
  End If

  '-- Return the enum description/name
  Return desc
End Function
[/codesnippet]