添加项目文件。

UIShare/Converters/TimeSpanToStringConverter.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Data;
+
+namespace UIShare.Converters
+{
+    public class TimeSpanToStringConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            if (value is TimeSpan timeSpan)
+            {
+                // 如果天数大于0，则显示天数
+                if (timeSpan.Days > 0)
+                {
+                    return $"{timeSpan.Days}天{timeSpan.Hours:D2}:{timeSpan.Minutes:D2}:{timeSpan.Seconds:D2}";
+                }
+                else
+                {
+                    // 如果不超过一天，则只显示时:分:秒
+                    return $"{timeSpan.Hours:D2}:{timeSpan.Minutes:D2}:{timeSpan.Seconds:D2}";
+                }
+            }
+
+            return "00:00:00";
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            // 通常不需要从字符串转换回TimeSpan，所以这里返回UnsetValue
+            return System.Windows.DependencyProperty.UnsetValue;
+        }
+    }
+}