mmxg.cs

这是本人学习语言来第一次写的程序

		}

		private void button2_Click(object sender, System.EventArgs e)
		{
			if(this.button2.Text == "重填")
			{
				this.textBox1.Text="";
				this.textBox2.Text="";
				this.textBox3.Text="";
				this.textBox4.Text="";
				this.textBox1.Focus();
			}
			else
			{
				this.Close();
			}
		}

		private void button1_Click(object sender, System.EventArgs e)
		{
			try
			{
				System.Data.OleDb.OleDbCommand MySelect = this.oleDbConnection1.CreateCommand();
				MySelect.CommandText = "SELECT 用户名 FROM ygxxb WHERE 用户名='"+this.textBox1.Text+"' and 密码='"+this.textBox2.Text+"'";
				this.oleDbDataAdapter1.SelectCommand = MySelect;

				System.Data.OleDb.OleDbCommand MyUpdata = this.oleDbConnection1.CreateCommand();
				MyUpdata.CommandText = "UPDATE ygxxb SET 密码='"+this.textBox3.Text+"' WHERE 用户名='"+this.textBox1.Text+"'";
				this.oleDbDataAdapter1.UpdateCommand = MyUpdata;

				if(this.textBox1.Text == "")
				{
					MessageBox.Show("请输入用户名！！！","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Information);
					this.textBox1.Focus();
				}
				else
				{
					if(this.textBox2.Text == "")
					{
						MessageBox.Show("请输入当前密码，否则无权修改密码！！！","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Exclamation);
						this.textBox2.Focus();
					}
					else
					{
						if(this.textBox3.Text == "")
						{
							MessageBox.Show("为了安全，请输入新密码！！！","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Information);
							this.textBox3.Focus();
						}
						else
						{
							if(this.textBox3.Text != this.textBox4.Text)
							{
								MessageBox.Show("两次密码不一样！重新输入．","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Exclamation);
								this.textBox4.Focus();
							}
							else
							{
								this.oleDbConnection1.Open();
								int If=this.oleDbDataAdapter1.Fill(this.dataSet21,"ygxxb");
								this.oleDbConnection1.Close();
								if( If== 0)
								{
									MessageBox.Show("当前密码错误，你无权修改！！！","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Exclamation);
									this.Close();
								}
								else
								{
									this.oleDbConnection1.Open();
									MyUpdata.ExecuteNonQuery();
									this.oleDbConnection1.Close();
									MessageBox.Show("密码修改成功，请记住你的新密码．","修改提示：",MessageBoxButtons.OK,MessageBoxIcon.Information);
									this.Close();
								}
							}
						}
					}
				}
			}
			catch(Exception Exc)
			{
				MessageBox.Show(Exc.Message);
				this.oleDbConnection1.Close();
			}
		}

		private void button1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
		{
			int Key=(int)e.KeyCode;
			switch(Key)
			{
				case 27:
					this.Close();					
					break;
				case 13:
					this.button1_Click(null,null);
					break;
				case 38:
				case 37:
					if(this.textBox1.Focused)
					{
						this.button2.Focus();
					}
					else
					{
						if(this.textBox2.Focused)
						{
							this.textBox1.Focus();
						}
						else
						{
							if(this.textBox3.Focused)
							{
								this.textBox2.Focus();
							}
							else
							{
								if(this.textBox4.Focused)
								{
									this.textBox3.Focus();
								}
								else
								{
									if(this.button1.Focused)
									{
										this.textBox4.Focus();
									}
									else
									{
										if(this.button2.Focused)
										{
											this.button1.Focus();
										}
									}
								}
							}
						}
					}
					break;
				case 40:
				case 39:
					if( this.textBox1.Focused)
					{
						this.textBox2.Focus();
					}
					else
					{
						if( this.textBox2.Focused)
						{
							this.textBox3.Focus();
						}
						else
						{
							if( this.textBox3.Focused)
							{
								this.textBox4.Focus();
							}
							else
							{
								if( this.textBox4.Focused)
								{
									this.button1.Focus();
								}
								else
								{
									if(this.button1.Focused)
									{
										this.button2.Focus();
									}
								}
							}
						}
					}
					break;
			}
		}
	}
}