C#控制台 统计用户输入的一串数字中每个数字出现的次数

曾经微软的面试考题！

下面是控制台编码！   窗体代码研制中……

 

class Program
    {
        static void Main(string[] args)
{
            //计算用户输入的一串数字中每个数字出现的次数

            Console.WriteLine("请输入一串数字");
            string str = Console.ReadLine();

            //将字符串转换为字符数组
            char[] chnum = str.ToCharArray();

            #region 判断用户输入的是否是数字
            for (int i =0; i < chnum.Length; i++)
            {//判断每一个字符是否是数字  通过char的方法来判断
                if (!char.IsNumber(chnum[i]))
                {
                    Console.WriteLine("您的输入有误，请输入数字");
                    Console.ReadKey();
                    return;
                }
            }

            #endregion

            //定义一个新的数组来保存计数
             int[] count=newint[9];

             #region for循环遍历
             //for循环遍历
             for (int i =0; i < chnum.Length; i++)
             {
                 switch (chnum[i])
                 {
                     case '1':
                         count[0]++;
                         break;
                     case '2':
                         count[1]++;
                         break;
                     case '3':
                         count[2]++;
                         break;
                     case '4':
                         count[3]++;
                         break;
                     case '5':
                         count[4]++;
                         break;
                     case '6':
                         count[5]++;
                         break;
                     case '7':
                         count[6]++;
                         break;
                     case '8':
                         count[7]++;
                         break;
                     case '9':
                         count[8]++;
                         break;
                 }
             }
             #endregion

            #region 循环输出
            for (int i =0; i < count.Length; i++)
            {
                Console.WriteLine("含有的数字 {0} 的个数是：{1}", i +1, count[i]);
            }
            #endregion
            Console.ReadKey();

        }

 

 

网上搜到的控制台代码！正确性不保证，留下来研究一下！

ArrayList list = new ArrayList();
            int EveNum = 0;
            foreach (var item in textBox1.Text.Trim())
            {
                if (!list.Contains(item))
                {
                    list.Add(item);
                }
            }

            foreach (var f in list)
            {
                EveNum = 0;
foreach (var z in textBox1.Text.Trim())
                {
                    if (f.ToString() == z.ToString())
                    {
                        EveNum++;                   
                    }
                  
           }
                textBox2.Text += f.ToString() + "," + EveNum.ToString() + "次"+"n";
                   

            }    

         以下方法是由上面方法变化而来了

             textBox2.Text = "";
            ArrayList list = new ArrayList();
            int EveNum = 0;
            foreach (var item in textBox1.Text.Trim())
            {
                if (!list.Contains(item))
                {
                    list.Add(item);
                    EveNum = 0;
                    foreach (var z in textBox1.Text.Trim())
                    {
                        if (item.ToString() == z.ToString())
                        {
                            EveNum++;
                        }

                    }
                    textBox2.Text += item.ToString() + "," + EveNum.ToString() + "次" + "\r\n";
                }
            }