C# Font.ToUIFont方法代码示例

 /// <summary>
 /// Gets height for the font.
 /// </summary>
 /// <param name="font">Font whose height is calculated.</param>
 /// <returns>Height of the font in inches.</returns>
 public double GetHeight(Font font)
 {
     return font.ToUIFont().Ascender 
         * UIScreen.MainScreen.Scale 
         * this.display.ScreenHeightInches() 
         / this.display.Height;
 }

		public static void UpdateFromFormsControl (this UILabel uiLabel, string text, TextAlignment textAlignment, Color textColor, Font font)
		{
			uiLabel.Text = text;
			uiLabel.TextAlignment = textAlignment.ToUITextAlignment ();
			uiLabel.TextColor = textColor.ToUIColor ();
			uiLabel.Font = font.ToUIFont ();
		}

		/// <summary>
		/// Adds the text.
		/// </summary>
		/// <param name="source">The source.</param>
		/// <param name="text">The text.</param>
		/// <param name="point">The point.</param>
		/// <param name="font">The font.</param>
		/// <param name="color">The color.</param>
		/// <returns>Task&lt;ImageSource&gt;.</returns>
		public static async Task<ImageSource> AddText(
			this StreamImageSource source,
			string text,
			CGPoint point,
			Font font,
			Color color)
		{
			var token = new CancellationTokenSource();
			var stream = await source.Stream(token.Token);
			var image = UIImage.LoadFromData(NSData.FromStream(stream));

			var bytes = image.AddText(text, point, font.ToUIFont(), color.ToUIColor()).AsPNG().ToArray();

			return ImageSource.FromStream(() => new MemoryStream(bytes));
		}

		public static void UpdateFromFormsControl (this UILabel uiLabel, string text, Xamarin.Forms.TextAlignment textAlignment, Color textColor, Font font)
		{
			uiLabel.Text = text;

			switch (textAlignment) {
			case TextAlignment.Start:
				uiLabel.TextAlignment = UITextAlignment.Left;
				break;
			case TextAlignment.Center: 
				uiLabel.TextAlignment = UITextAlignment.Center;
				break;
			case TextAlignment.End: 
				uiLabel.TextAlignment = UITextAlignment.Right;
				break;
			}

			uiLabel.TextColor = textColor.ToUIColor ();
			uiLabel.Font = font.ToUIFont ();
		}

        public double GetHeight(Font font)
        {
            var height = (double)string.Empty.StringHeight(font.ToUIFont(), float.MaxValue);

            return height * this.display.ScreenHeightInches() / this.display.Height;
        }