请高手帮我看看这个c#程序有什么错

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace 计时器
{
    public partial class Form1 : Form
    {
        uint remainder;
        uint minute;
        uint second;
        string msg;
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void textBox3_AcceptsTabChanged(object sender, EventArgs e)
        {

        }

        private void Form1_Activated(object sender, EventArgs e)
        {
            textBox3.Focus();
        }


        private void timer1_Tick(object sender, EventArgs e)
        {
            textBox1.Text=DateTime.Now.Hour.ToString()+"："+DateTime.Now.Minute.ToString()+"："+DateTime.Now.Second.ToString();
        }

        private void timer2_Tick(object sender, EventArgs e)
        {
            textBox2.Text=DateTime.Now.Hour.ToString()+"："+DateTime.Now.Minute.ToString()+"："+DateTime.Now.Second.ToString();
            remainder--;
            minute=remainder/60;
            second=remainder%60;
            if(second<10)
                msg="剩余时间："+minute+"分0"+second+"秒";
            else
                msg="剩余时间："+minute+"分"+second+"秒";
            label5.Text=msg;
            if(remainder==0)
            {
                timer1.Enabled=false;
                label5.Text+="--时间到！！";
            }

        }

        private void button1_Click(object sender, EventArgs e)
        {
            label5.Text="";
            textBox3.Text="";
            textBox3.Focus();
            timer2.Enabled=true;
        }

        private void textBox3_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar ='\r')
            {
                if (textBox3.Text ="")
                    return;
                remainder = Convert.ToUInt32(textBox3.Text) * 60;
                timer1.Enabled = false;
                timer2.Enabled = true;
                label1.Text = "开始时间";
            }
        }


    }
} --------------------编程问答-------------------- 汗，同一个问题竟发了两个帖子，而且均是0分帖！！！

--------------------编程问答-------------------- 好长

补充：.NET技术 ,  C#