一个c#写的能识别四则表达式运算的程序

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;//Download by http://down.liehuo.netusing System.Data.SqlClient;namespace Case05_12{ public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { try { //生成连接数据库字符串 string ConStr = "data source=.;database=ljp;uid=sa;pwd=123"; //定义SqlConnection对象实例 SqlConnection con = new SqlConnection(ConStr); //定义Select查询语句 string Sql = "select*from biaoge"; SqlDataAdapter ada = new SqlDataAdapter(Sql, con); DataSet ds = new DataSet(); //定义DataSet对象实例 ada.Fill(ds); //连接数据表格，显示数据 this.dataGridView1.DataSource = ds.Tables[0].DefaultView; } catch { return; } } private void button2_Click(object sender, EventArgs e) { this.Close(); Application.Exit(); } }}

STM32F103工程模板,免去开发者创建库函数模板的烦老

4th exercise of computer graphics course

1、自定义站点信息。（地址、名称、邮件等……） 2、自定义站点版权信息。 3、自定义页面位置风格。 4、随意更新移动文本公告。 5、控制页面广告。 6、控制访问者留言发布模式（直接显示/验证）。(1, custom site information. (Address, name, e-mail and so on ......) 2, custom site copyright information. 3, custom page style position. 4, free to move text update bulletin. 5, control pages advertising. 6, the control Visitor Messages release mode (direct display/verification).)

说明：  This is programm solved cicle with PI number

低频信号先进行放大，再调制解调，设计发射(Low-frequency signal is first amplified, and then modulation and demodulation, the transmitter )

DES - Cryptograther using c#

Thread Templete Class Custom Thread

说明：  使用esp-8266WIFI模块和路由器以及一个终端相连，然后使用STM32单片机测量频率并发出(Use esp-8266 WIFI module to connect with router and a terminal, then use STM32 MCU to measure frequency and send it out.)

hash_table的c语言的链表实现。包括一个简单的hash函数和hash_table的源码。(hash_table c language linked list implementation. Includes a simple hash function and hash_table source.)