} }
控制台程序，学生排序
namespace ch2Exe {
class Program {
static void Main(string[] args) {
String[,] Score = new String[5, 3];
Console.WriteLine(\请输入姓名，学号和C#课程的考试成绩(以回车键结束！)：\); for (int i = 0; i < 5; i++) {
Console.WriteLine(\第{0}个学生：\, i); for (int j = 0; j < 3; j++) {
Score[i, j] = Console.ReadLine();
} }
//排序算法
for (int i = 0; i < 4; i++) {
for (int j = i+1; j < 5; j++) {
if(double.Parse ( Score [i,2])>=double.Parse ( Score [j,2])) {//交换两个成绩的位置，同时交换姓名和学号的位置 string temp;
for (int k = 0; k < 3; k++) {
temp = Score[i, k];
Score[i, k] = Score[j, k]; Score[j, k] = temp;
} }
} }
//输出结果
Console.WriteLine(\姓名 学号 课程的考试成绩\); for (int i = 0; i < 5; i++) {
for (int j = 0; j < 3; j++) {
Console.Write(Score[i, j]+\);
}
Console.WriteLine(\); }
Console.ReadKey(); }
} }
Using 命令
namespace 计算器 //本程序有很多重复啰唆的地方，以后有时间再改！ {
public partial class Form1 : Form {
public double dblFirst = 0; public double dblSecond = 0; public bool blnFirstOpen = true; public bool blnClear = false; public string strOper; public Form1() {
InitializeComponent(); }
private void button0_Click_1(object sender, EventArgs e) {
if (sender == button0) append_num(0); }
private void button4_Click(object sender, EventArgs e) {
if (sender == button4) append_num(1); }
private void button8_Click(object sender, EventArgs e) {
if (sender == button8) append_num(2); }
private void button12_Click(object sender, EventArgs e) {
if (sender == button12) append_num(3); }
private void button3_Click(object sender, EventArgs e) {
if (sender == button3) append_num(4); }
private void button7_Click(object sender, EventArgs e) {
if (sender == button7) append_num(5); }
private void button11_Click(object sender, EventArgs e) {
if (sender == button11) append_num(6); }
private void button2_Click(object sender, EventArgs e) {
（计算器）
if (sender == button2) append_num(7); }
private void button6_Click(object sender, EventArgs e) {
if (sender == button6) append_num(8); }
private void button10_Click(object sender, EventArgs e) {
if (sender == button10) append_num(9); }
private void append_num(int i) {
if(blnClear) {
if(blnFirstOpen==true)
dblFirst=Convert.ToDouble(textBox1.Text); else
dblSecond=Convert.ToDouble(textBox1.Text); textBox1.Text=\; blnClear=false; }
if(((i==0)&&(textBox1.Text!=\))||(i!=0)) textBox1.Text=textBox1.Text+i.ToString(); }
private void btn_equ_Click_1(object sender, EventArgs e)//等号的处理 {
if (textBox1.Text != \)
if (blnFirstOpen == true)
dblFirst = Convert.ToDouble(textBox1.Text); else
dblSecond = Convert.ToDouble(textBox1.Text); switch (strOper) {
case \:
dblFirst += dblSecond; break; case \:
dblFirst -= dblSecond; break; case \:
dblFirst *= dblSecond; break; case \:
dblFirst /= dblSecond; break; }
strOper = \;
blnFirstOpen = false;
textBox1.Text = Convert.ToString(dblFirst); blnClear = true; }
private void btn_clear_Click(object sender, EventArgs e)//清空文本框 {
dblFirst = 0; dblSecond = 0;
blnFirstOpen = true; blnClear = false; textBox1.Text = \; textBox1.Focus(); }
private void btn_dot_Click_1(object sender, EventArgs e)//小数点的处理办法 {
if (textBox1.Text == \) textBox1.Text = \;
else if(textBox1.Text==\)
MessageBox.Show(\小数不能函数两个小数点！\); else
textBox1.Text = textBox1.Text + \; blnClear = false; }
private void btn_plus_Click_1(object sender, EventArgs e)//加法的实现函数 {
if (textBox1.Text != \)
if (blnFirstOpen == true)
dblFirst = Convert.ToDouble(textBox1.Text); else
dblSecond = Convert.ToDouble(textBox1.Text);
if (sender == btn_plus) strOper = \;
else if (sender == btn_minus) strOper = \; if (sender == btn_mul) strOper = \; if (sender == btn_div) strOper = \; blnFirstOpen = false;
textBox1.Text = Convert.ToString(dblFirst); blnClear = true; }
private void btn_minus_Click(object sender, EventArgs e)//减法的实现函数 {
if (textBox1.Text != \)
if (blnFirstOpen == true)
dblFirst = Convert.ToDouble(textBox1.Text); else
dblSecond = Convert.ToDouble(textBox1.Text);
if (sender == btn_plus) strOper = \;
else if (sender == btn_minus) strOper = \; if (sender == btn_mul) strOper = \; if (sender == btn_div) strOper = \; blnFirstOpen = false;
textBox1.Text = Convert.ToString(dblFirst); blnClear = true; }
private void btn_mul_Click(object sender, EventArgs e)//乘法的实现函数 {
if (textBox1.Text != \)
if (blnFirstOpen == true)
dblFirst = Convert.ToDouble(textBox1.Text); else
dblSecond = Convert.ToDouble(textBox1.Text);
if (sender == btn_plus) strOper = \;
else if (sender == btn_minus) strOper = \; if (sender == btn_mul) strOper = \; if (sender == btn_div) strOper = \; blnFirstOpen = false;
textBox1.Text = Convert.ToString(dblFirst); blnClear = true; }
private void btn_div_Click(object sender, EventArgs e)//除法的实现 {
if (textBox1.Text != \)
if (blnFirstOpen == true)
dblFirst = Convert.ToDouble(textBox1.Text); else
dblSecond = Convert.ToDouble(textBox1.Text);
if (sender == btn_plus) strOper = \;
else if (sender == btn_minus) strOper = \; if (sender == btn_mul) strOper = \; if (sender == btn_div) strOper = \; blnFirstOpen = false;
textBox1.Text = Convert.ToString(dblFirst); blnClear = true; }
} }
（显示）
private void XS_Click(object sender, EventArgs e)
{ //显示
SqlConnection cnn = new SqlConnection(); cnn.ConnectionString = cnntxt.Text; DataSet ds = new DataSet(); string sqlstr = sqltxt.Text;
SqlDataAdapter da = new SqlDataAdapter(sqlstr, cnn); da.Fill(ds, \);
dgw.DataSource = ds.Tables[\]; }