Convert string to Brushes/Brush color name in C#

问题:

I have a configuration file where a developer can specify a text color by passing in a string:

 <text value="Hello, World" color="Red"/>

Rather than have a gigantic switch statement look for all of the possible colors, it'd be nice to just use the properties in the class System.Drawing.Brushes instead so internally I can say something like:

 Brush color = Brushes.Black;   // Default

 // later on...
 this.color = (Brush)Enum.Parse(typeof(Brush), prasedValue("color"));

Except that the values in Brush/Brushes aren't enums. So Enum.Parse gives me no joy. Suggestions?

回答1:

Recap of all previous answers, different ways to convert a string to a Color or Brush:

// best, using Color's static method
Color red1 = Color.FromName("Red");

// using a ColorConverter
TypeConverter tc1 = TypeDescriptor.GetConverter(typeof(Color)); // ..or..
TypeConverter tc2 = new ColorConverter();
Color red2 = (Color)tc.ConvertFromString("Red");

// using Reflection on Color or Brush
Color red3 = (Color)typeof(Color).GetProperty("Red").GetValue(null, null);

// in WPF you can use a BrushConverter
SolidColorBrush redBrush = (SolidColorBrush)new BrushConverter().ConvertFromString("Red");

回答2:

String to brush:

myTextBlock.Foreground = new BrushConverter().ConvertFromString("#FFFFFF") as SolidColorBrush;

That's my case here!

回答3:

A brush can be declared like this

Brush myBrush = new SolidBrush(Color.FromName("Red"));

回答4:

D'oh. After a while of looking I found:

 Color.FromName(a.Value)

After hitting "post". From there it's a short step to:

 color = new SolidBrush(Color.FromName(a.Value));

I'll leave this question here for others....

回答5:

You could use reflection for this:

Type t = typeof(Brushes);
Brush b = (Brush)t.GetProperty("Red").GetValue(null, null);

Of course, you'll want some error handling/range checking if the string is wrong.

回答6:

I agree that using TypeConverters are the best method:

 Color c = (Color)TypeDescriptor.GetConverter(typeof(Color)).ConvertFromString("Red");
 return new Brush(c);

回答7:

Try using a TypeConverter. Example:

var tc = TypeDescriptor.GetConverter(typeof(Brush));

Another alternative is to use reflection, and go over the properties in SystemBrushes.

回答8:

If you want, you can extend this even more and allow them to specify values for the R, G and B values. Then you just call Color.FromArgb(int r, int g, int b);

回答9:

You can use System.Drawing.KnownColor enum. It specifies all known system colors.