private void button1_Click(object sender, EventArgs e)

  {
    String name = this.textBox1.Text; // 獲取里面的值
    String password = this.textBox1.Text;
    if (name.Equals("admin") && password.Equals("admin")) // 判斷賬號(hào)密碼是否等于admin
    {
      MessageBox.Show("登錄成功");
    }
    else {
      MessageBox.Show("登錄失敗！");
    }
  }

 //限定用戶名必須為字母
     private void txtName_KeyPress(object sender, KeyPressEventArgs e)
     {
       if ((e.KeyChar >= 'a' && e.KeyChar <= 'z') || (e.KeyChar >= 'A' && e.KeyChar <= 'Z'))
       {
         e.Handled = false;
       }
       else {
         MessageBox.Show("用戶名只能為字母！");
         e.Handled = true;
       }
     }

  //光標(biāo)進(jìn)入文本框時(shí)，背景為藍(lán)色，字體為白色；
     //光標(biāo)離開文本框時(shí)，背景為白色，字體為黑色。
     private void txtName_Enter(object sender, EventArgs e)
     {
       txtName.ForeColor = Color.White;
       txtName.BackColor = Color.Blue;
     }
 
     private void txtName_Leave(object sender, EventArgs e)
     {
       txtName.BackColor = Color.White;
       txtName.ForeColor = Color.Black;
     }

private void btnLogin_Click(object sender, EventArgs e)
    {
      string userName = txtName.Text;
      string password = txtPwd.Text;
      if (userName == "admin" && password == "123")
      {
        MessageBox.Show("歡迎進(jìn)入個(gè)人理帳系統(tǒng)！", "登陸成功！", MessageBoxButtons.OK, MessageBoxIcon.Information);
      }
      else
      {
        MessageBox.Show("您輸入的用戶名或密碼錯(cuò)誤！", "登錄失??！", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
      }
    }

 private void btnCancel_Click(object sender, EventArgs e)
    {
      txtName.Text = "";
      txtPwd.Text = "";
      txtName.Focus();
    }