If you have written any .NET components you must be familiar with Category and Description attributes. We use Category attribute to identify the property’s category and Description attribute is for the short description of that property. But because of the nature of Attributes in .NET we cannot pass any parameter to these attributes for Multilanguage support.
[Category(Properties.Resources.MyCategory)]
[Description(Properties.Resources.MyDescription)]
public int MyProperty { … }
This kind of usage is not allowed for .NET, because we are only allowed to give constant values to the attributes constructor. So how can we use these attributes as Multilanguage?
Solution is simple;
Deriving two new attributes from
Category and
Description attributes will handle our problem. Because
PropertyGrid uses
PropertyDescriptors which resolves properties description and category from these two attributes, so if we derived our new attributes from
DescriptionAttribute and
CategoryAttribute this will also continue to work for
PropertyGrid and all kind of grids which uses
PropertyDescriptors.
Our new attributes will be;
[AttributeUsage(AttributeTargets.All)]
internal class SRDescriptionAttribute : DescriptionAttribute
{
bool ps = false;
public SRDescriptionAttribute(string description) : base(description)
{ }
public override string Description
{
get
{
if (!ps)
{
ps = true;
// Here we read the multilanguaged text from the resources
// by using given Description text as Key
base.DescriptionValue = Properties.Resources.ResourceManager.GetString(base.Description);
}
return base.Description;
}
}
}
[AttributeUsage(AttributeTargets.All)]
internal sealed class SRCategoryAttribute : CategoryAttribute
{
public SRCategoryAttribute(string category) : base(category)
{ }
protected override string GetLocalizedString(string value)
{
// Here we read the multilanguaged text from the resources
// by using given Category text as Key
return Properties.Resources.ResourceManager.GetString(value);
}
}
|
Now we can use these attributes. The only thing that we have to do is giving the resource names as the description and category to the attributes.
Usage:
[SRCategory(“Cat_MyCategory”)]
[SRDescription(“Des_MyProperty”)]
public int MyProperty { … }
* Cat_MyCategory and Des_MyProperty are the names of resources in the resource file.
Actually as you see, for the Category attribute GetLocalizedString method and for the Description attribute Description property were both was written as virtual, which means that derived classes can override them (They wish 
so).