public static class ArrHelper
{
        /// <summary>
        /// 對類型為T的數組進行擴展，把滿足條件的元素移動到數組的最前面
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="arr">源數組</param>
        /// <param name="match">lamda表達式</param>
        /// <returns></returns>
        public static bool MoveToFront<T>(this T[] arr, Predicate<T> match)
        {
            //如果數組的長度為0
            if (arr.Length == 0)
            {
                return false;
            }
            //獲取滿足條件的數組元素的索引
            var index = Array.FindIndex(arr, match);
            //如果沒有找到滿足條件的數組元素
            if (index == -1)
            {
                return false;
            }
            //把滿足條件的數組元素賦值給臨時變量
            var temp = arr[index];
            Array.Copy(arr, 0, arr, 1, index);
            arr[0] = temp;
            return true;
        }
        public static void PrintArray<T>(T[] arr)
        {
            foreach (var item in arr)
            {
                Console.Write(item + " ");
            }
            Console.WriteLine();
        }
}

class Program
{
        static void Main(string[] args)
        {
            int[] intArr = new int[]{1, 2, 3, 4, 5};
            ArrHelper.PrintArray(intArr);
            intArr.MoveToFront(i => i == 3);
            ArrHelper.PrintArray(intArr);
            Console.ReadKey();
        }
}