包含vb.net测试程序实例的词条

用VB.NET编写以下程序。

using System;

using System.Windows.Forms;

namespace WindowsFormsApplication1

{

    public partial class Form1 : Form

    {

        Timer tm = new Timer();//实例化 timeer 

        static int timeS = 0; //设置静态变量记录秒数

        TimeSpan ts = new TimeSpan(); //实例化 TimeSpan 

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            tm.Interval = 1000; //设置 timeer 1000毫秒执行一次

            tm.Tick += new EventHandler(timeer_Tick); //设置 timeer 运行事件

            tm.Start(); // 启用 timeer

        }

        private void timeer_Tick(object sender, EventArgs e)

        {

            timeS += 1; //秒数 +1 

            ts = new TimeSpan(0, 0, timeS); 

            label1.Text = ts.Hours + ":" + ts.Minutes + ":" + ts.Seconds;

            

        }

        private void button2_Click(object sender, EventArgs e)

        {

            tm.Stop();

            timeS = 0;

        }

    }

}

相关问答

Q1: VB.net生成单个实例应用程序

就是只允许启动单一个应用程序的实例, 试图启动第二次时不会产生新的实例,并激活已经启动的实例.

Q2: 关于VB.NET进度条的实例

该实例有很多实现方法,下面介绍一种不同的给你:

首先要在窗体中载入以下控件:progressbar(进度条),label(用来实时显示文本提示),两个timer(分别控制进度条进度的增减),然后用以下代码就能实现:

Public Class Form1

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Timer1.Enabled = True

Timer1.Interval = 500

Timer2.Interval = 500

ProgressBar1.Value = 0

ProgressBar1.Maximum = 100

ProgressBar1.Minimum = 0

End Sub

'上述过程是设置控件的初始值,也可以在属性面板设置

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick

ProgressBar1.Value += 1

Label1.Text = "当前完成" ProgressBar1.Value "%"

If (ProgressBar1.Value = 100) Then

Timer1.Enabled = False

Timer2.Enabled = True

End If

End Sub

'timer1用来控制进度的增加

Private Sub Timer2_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer2.Tick

ProgressBar1.Value -= 1

Label1.Text = "当前完成" ProgressBar1.Value "%"

If (ProgressBar1.Value = 0) Then

Timer1.Enabled = True

Timer2.Enabled = False

End If

End Sub

'time2用来控制进度的减少

End Class