Neglected to add a file

Font measurement helper functions.

CommonWPF/Helper.cs

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2019 faddenSoft
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Media;
+
+namespace CommonWPF {
+    /// <summary>
+    /// Miscellaneous helper functions.
+    /// </summary>
+    public static class Helper {
+        /// <summary>
+        /// Measures the size of a string when rendered with the specified parameters.  Uses
+        /// the current culture, left-to-right flow, and 1 pixel per DIP.
+        /// </summary>
+        /// <remarks>
+        /// The Graphics.MeasureString approach from WinForms doesn't work in WPF, but we can
+        /// accomplish the same thing with the FormattedText class.
+        /// </remarks>
+        /// <seealso cref="https://stackoverflow.com/a/9266288/294248"/>
+        /// <param name="str">Text to be displayed.</param>
+        /// <param name="fontFamily">Font family for Typeface.</param>
+        /// <param name="fontStyle">Font style for Typeface.</param>
+        /// <param name="fontWeight">Font weight for Typeface.</param>
+        /// <param name="fontStretch">Font stretch for Typeface.</param>
+        /// <param name="emSize">Font size.</param>
+        /// <returns>Width and height of rendered text.</returns>
+        public static Size MeasureString(string str, FontFamily fontFamily, FontStyle fontStyle,
+                FontWeight fontWeight, FontStretch fontStretch, double emSize) {
+            FormattedText fmt = new FormattedText(
+                str,
+                CultureInfo.CurrentCulture,
+                FlowDirection.LeftToRight,
+                new Typeface(fontFamily, fontStyle, fontWeight, fontStretch),
+                emSize,
+                Brushes.Black,
+                new NumberSubstitution(),
+                1.0);
+
+            return new Size(fmt.Width, fmt.Height);
+        }
+
+        /// <summary>
+        /// Measures the size of a string when rendered with the specified parameters.  Uses
+        /// the current culture, left-to-right flow, and 1 pixel per DIP.
+        /// </summary>
+        /// <param name="str">Text to be displayed.</param>
+        /// <param name="typeface">Font typeface to use.</param>
+        /// <param name="emSize">Font size.</param>
+        /// <returns>Width of rendered text.</returns>
+        public static double MeasureStringWidth(string str, Typeface typeface, double emSize) {
+            FormattedText fmt = new FormattedText(
+                str,
+                CultureInfo.CurrentCulture,
+                FlowDirection.LeftToRight,
+                typeface,
+                emSize,
+                Brushes.Black,
+                new NumberSubstitution(),
+                1.0);
+
+            return fmt.Width;
+        }
+    }
+}