How to assign multiple enum values to a property in Spring.NET configuration?
.NET supports the FlagsAttribute for enum's, which indicates "that an enumeration can be treated as a bit field".
An example of an enum that makes use of this [Flags] attribute is System.Windows.Forms.Keys
Here is my Spring.NET object definition:
<object id="command.paste" type="MyNamespace.PasteClipboardCommand, MyProject">
<property name="Title" value="Paste into Folder" />
<property name="ShortcutKeys" value="P" />
</object>
This sets the property ShortcutKeys of type Keys to the key P. No problem there. However, since this is a shortcut, I'd like to assign something like Control+P as shortcut key.
If I would wire this up in code, it would be:
command.ShortcutKeys = Keys.Control | Keys.P;
So, maybe I was a little naive trying this:
<property name="ShortcutKeys" value="Control|P" />
This fails, because the EnumConverter can only parse/convert string representations of single enum's. A full stacktrace is available below.
- Is this possible by default Spring.NET ?
- Can I work around this by specifying/using another EnumConverter ?
- Should I create/use another Keys class to do the Spring.NET initialization ?
UPDATE:
Apparently the KeysConverter knows how to handle this like this:
(new KeysConverter()).ConvertFrom(null, null, "Control+P");
Unfortunately, the EnumConverter does not support this ?
Attached Stacktrace:
System.Configuration.ConfigurationErrorsException: Error creating context 'spring.root': PropertyAccessExceptionsException (1 errors); nested PropertyAccessExceptions are:
[Spring.Core.TypeMismatchException: Cannot convert property value of type [System.String] to required type [System.Windows.Forms.Keys] for property 'ShortcutKeys'., Inner Exception: System.FormatException: Control|P is not a valid value for Keys. ---> System.ArgumentException: Requested value 'Control|P' was not found.
at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase)
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
--- End of inner exception stack trace ---
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
at System.ComponentModel.TypeConverter.ConvertFromInvariantString(String text)
at Spring.Core.TypeConversion.TypeConversionUtils.ConvertValueIfNecessary(Type requiredType, Object newValue, String propertyName)] ---> Spring.Objects.Factory.ObjectCreationException: Error creating object with name 'command.builder.paste' defined in 'file [....\commands.xml] line 39' : Error setting property values: PropertyAccessExceptionsException (1 errors); nested PropertyAccessExceptions are:
[Spring.Core.TypeMismatchException: Cannot convert property value of type [System.String] to required type [System.Windows.Forms.Keys] for property 'ShortcutKeys'., Inner Exception: System.FormatException: Control|P is not a valid value for Keys. ---> System.ArgumentException: Requested value 'Control|P' was 开发者_开发百科not found.
at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase)
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
--- End of inner exception stack trace ---
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
at System.ComponentModel.TypeConverter.ConvertFromInvariantString(String text)
at Spring.Core.TypeConversion.TypeConversionUtils.ConvertValueIfNecessary(Type requiredType, Object newValue, String propertyName)] ---> PropertyAccessExceptionsException (1 errors); nested PropertyAccessExceptions are:
[Spring.Core.TypeMismatchException: Cannot convert property value of type [System.String] to required type [System.Windows.Forms.Keys] for property 'ShortcutKeys'., Inner Exception: System.FormatException: Control|P is not a valid value for Keys. ---> System.ArgumentException: Requested value 'Control|P' was not found.
at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase)
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
--- End of inner exception stack trace ---
at System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
at System.ComponentModel.TypeConverter.ConvertFromInvariantString(String text)
at Spring.Core.TypeConversion.TypeConversionUtils.ConvertValueIfNecessary(Type requiredType, Object newValue, String propertyName)]
If you look at the Spring.NET documentation 5.11 Configuration of IApplicationContext, you can see an example of how to add a specific type converter for a given type.
Adding the KeysConverter for type Keys in app.config is sufficient:
<converter for="System.Windows.Forms.Keys, System.Windows.Forms" type="System.Windows.Forms.KeysConverter, System.Windows.Forms"/>
Now the enumvalue/shortcut can be specified like this:
<property name="ShortcutKeys" value="Control+P" />
Try using SpEL (Spring.NET Expression Language) : http://www.springframework.net/doc-latest/reference/html/expressions.html
<property name="ShortcutKeys" expression="Keys.Control or Keys.P" />
or
<property name="ShortcutKeys" expression="T(System.Windows.Forms.Keys).Control or T(System.Windows.Forms.Keys).P" />
<property name="ShortcutKeys" value="Control, P" />
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