c# - 以编程方式从 Brushes 类中获取画笔？

Question

我有一个属性允许将已知颜色的字符串名称发送到我的控件。该属性只接受正确的已知颜色名称，如“红色”或“蓝色”

  private KnownColor _UseColor = KnownColor.Red;

    /// <summary>
    /// Gets or sets the name of the colour
    /// </summary>
    public string ColorName
    {
        get
        {
            return this._UseColor.ToString();
        }
        set
        {
            if (Enum.IsDefined(typeof(KnownColor), value))
                this._UseColour = (KnownColor)Enum.Parse(typeof(KnownColor), value);
        }
    }

我想做的是使用此 _UseColour 枚举从静态 Brushes 中选择一个现有画笔像这样在 .NET 中上课

Brush sysBrush = Brushes.FromKnownColor(this._UseColor);
e.Graphics.FillRectangle(sysBrush, 0, 0, 10, 10);

而不是每当像这样绘制控件时都创建一个新画笔

using (SolidBrush brsh = new SolidBrush(Color.FromKnownColor(this._UseColor)))
    e.Graphics.FillRectangle(brsh, 0, 0, 10, 10);

有谁知道这是否可行，或者我每次都必须创建一个新画笔吗？

Brushes.FromKnownColor 不是 Brushes 类中的方法

Answer 1

为什么不创建一次画笔并将其缓存以备后用？

在你的主类中:

private KnownColor _UseColor = KnownColor.Red;

/// <summary>
/// Gets or sets the name of the colour
/// </summary>
public string ColorName
{
    get
    {
        return this._UseColor.ToString();
    }
    set
    {
        if (Enum.IsDefined(typeof(KnownColor), value))
            this._UseColour = (KnownColor)Enum.Parse(typeof(KnownColor), value);
    }
}

private Dictionary<string, Brush> _knownBrushes = new Dictionary<string, Brush>();

public Brush ColorBrush
{
    get
    {
        if (!_knownBrushes.ContainsKey(_UseColor)) {
            _knownBrushes[_UseColor] = new SolidBrush(Color.FromKnownColor(this._UseColor));
        }

        return _knownBrushes[_UseColor];
    }
}

然后像...一样使用它

e.Graphics.FillRectangle(ColorBrush, 0, 0, 10, 10);