功能1：

TextBox控件，只允许输入正负数字和小数，且小数点只能后两位

功能2： 

winform控件启动线程，执行任务

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;namespace WinFormsAppProject
{public partial class Form1 : Form{public Form1(){InitializeComponent();}/// <summary>/// winform 多个textbox只能输入小数 /// 选中控件，属性，右侧有个事件按钮，在下方keypress中选择绑定的事件/// 限制输入，只能输入正负数，且小数点后两位/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void RestrictInput(object sender, KeyPressEventArgs e){if ((e.KeyChar < 48 || e.KeyChar > 57) && e.KeyChar != 8 && e.KeyChar != (char)('.') && e.KeyChar != (char)('-')){e.Handled = true;}if (e.KeyChar == (char)('-')){if ((sender as TextBox).Text != ""){e.Handled = true;}}//第1位是负号时候、第2位小数点不可if (((TextBox)sender).Text == "-" && e.KeyChar == (char)('.')){e.Handled = true;}//负号只能1次if (e.KeyChar == 45 && (((TextBox)sender).SelectionStart != 0 || ((TextBox)sender).Text.IndexOf("-") >= 0))e.Handled = true;//第1位小数点不可if (e.KeyChar == (char)('.') && ((TextBox)sender).Text == ""){e.Handled = true;}//小数点只能1次if (e.KeyChar == (char)('.') && ((TextBox)sender).Text.IndexOf('.') != -1){e.Handled = true;}//小数点（最大到2位）   if (e.KeyChar != '\b' && (((TextBox)sender).SelectionStart) > (((TextBox)sender).Text.LastIndexOf('.')) + 2 && ((TextBox)sender).Text.IndexOf(".") >= 0)e.Handled = true;//光标在小数点右侧时候判断  if (e.KeyChar != '\b' && ((TextBox)sender).SelectionStart >= (((TextBox)sender).Text.LastIndexOf('.')) && ((TextBox)sender).Text.IndexOf(".") >= 0){if ((((TextBox)sender).SelectionStart) == (((TextBox)sender).Text.LastIndexOf('.')) + 1){if ((((TextBox)sender).Text.Length).ToString() == (((TextBox)sender).Text.IndexOf(".") + 3).ToString())e.Handled = true;}if ((((TextBox)sender).SelectionStart) == (((TextBox)sender).Text.LastIndexOf('.')) + 2){if ((((TextBox)sender).Text.Length - 3).ToString() == ((TextBox)sender).Text.IndexOf(".").ToString()) e.Handled = true;}}//第1位是0，第2位必须是小数点if (e.KeyChar != (char)('.') && e.KeyChar != 8 && ((TextBox)sender).Text == "0"){e.Handled = true;}}private void textBox1_KeyPress(object sender, KeyPressEventArgs e){RestrictInput(sender, e);}private void textBox2_KeyPress(object sender, KeyPressEventArgs e){RestrictInput(sender, e);}private void Form1_Load(object sender, EventArgs e){//初始化进度条progressBar1.Maximum = 100;progressBar1.Minimum = 0;progressBar1.Value = 0;}private void button1_Click(object sender, EventArgs e){//开启任务，异步执行，线程池线程，后台线程//窗体还可以拖动，不被阻塞func3();func1();func2();}private void button2_Click(object sender, EventArgs e){//无线程，阻塞UI线程func4();}private void button3_Click(object sender, EventArgs e){//System.InvalidOperationException:“线程间操作无效: 从不是创建控件“progressBar1”的线程访问它。”//可以在程序入口添加 Control.CheckForIllegalCrossThreadCalls = false; //设置不捕获线程异常 解决该问题func5();}private void button4_Click(object sender, EventArgs e){//使用this.BeginInvoke(new EventHandler(delegate{   }));执行异步访问ui线程。使用this.BeginInvoke(mi执行异步过程中不能拖动窗体func6();}private void button5_Click(object sender, EventArgs e){//使用System.Windows.Forms.Timer();;实现异步访问uifunc7();}private void button6_Click(object sender, EventArgs e){//使用Control.CheckForIllegalCrossThreadCalls = false;  再开启任务访问ui控件实现异步，异步执行过程中拖动窗体func5();func2();}private void button7_Click(object sender, EventArgs e){// this.BeginInvoke(mi)在创建控件的基础句柄所在线程上异步执行指定委托func6();和其他任务func2();实现异步。使用this.BeginInvoke(mi执行异步过程中不能拖动窗体func6();func2();}private void func1(){Task.Factory.StartNew(() => {for (int i = 0; i < 5; i++){Debug.WriteLine(i);System.Threading.Thread.Sleep(1000);}});}private void func2(){//开启任务并执行Task.Factory.StartNew(() => {for (int i = 100; i < 105; i++){Debug.WriteLine(i);System.Threading.Thread.Sleep(500);}});}private void func3(){//开启任务并执行Task.Factory.StartNew(() => {System.Threading.Thread.Sleep(5000);Debug.WriteLine(5000);});}//阻塞UI线程private void func4(){int i = 0;while (++i < 100){System.Threading.Thread.Sleep(30);//模拟耗时操作progressBar1.Value = i;}}#region 异步访问UI控件//使用线程访问ui控件时报错：System.InvalidOperationException:“线程间操作无效: 从不是创建控件“progressBar1”的线程访问它。”//可以在程序入口添加 Control.CheckForIllegalCrossThreadCalls = false; //设置不捕获线程异常 解决该问题private void func5(){progressBar1.Value = 0;//开启任务Task task = new Task(() =>{int i = 0;while (++i < 100){System.Threading.Thread.Sleep(30);//模拟耗时操作progressBar1.Value = i;}});task.Start();//执行任务}//使用MethodInvoker mi; this.BeginInvoke(mi)在创建控件的基础句柄所在线程上异步执行指定委托。//解决：System.InvalidOperationException:“线程间操作无效: 从不是创建控件“progressBar1”的线程访问它。”问题private void func6(){progressBar1.Value = 0;#region 使用BeginInvoke虽然解决了跨UI线程访问控件的问题，实现异步，但是涉及到控件访问的过程中，不能拖动窗体。使用 Task.Factory.StartNew()包多一层还是不能拖动窗体。。。。。//Task.Factory.StartNew(() =>//{//    //MethodInvoker mi = new MethodInvoker(() =>//    //{//    //    int i = 0;//    //    while (++i < 100)//    //    {//    //        System.Threading.Thread.Sleep(30);//模拟耗时操作//    //        progressBar1.Value = i;//    //    }//    //});//    //this.BeginInvoke(mi);//    this.BeginInvoke(new EventHandler(delegate//    {//        int i = 0;//        while (++i < 100)//        {//            System.Threading.Thread.Sleep(30);//模拟耗时操作//            progressBar1.Value = i;//        }//    }));//});#endregionthis.BeginInvoke(new EventHandler(delegate{int i = 0;while (++i < 100){System.Threading.Thread.Sleep(50);//模拟耗时操作progressBar1.Value = i;}}));}#endregion#region 使用System.Windows.Forms.Timer();;实现异步访问uiSystem.Windows.Forms.Timer t;private void func7(){t = new System.Windows.Forms.Timer();t.Tick += new EventHandler(TimerTick);//t.Interval = 30;//默认100t.Enabled = true;}private void TimerTick(object sender, EventArgs e){t.Stop();t.Dispose();int i = 0;while (++i < 100){System.Threading.Thread.Sleep(50);//模拟耗时操作progressBar1.Value = i;}}#endregion}
}