System.Windows.Forms.Control.Focus C# (CSharp) Method

		public bool Focus() {
			return FocusInternal (false);
		}

        public static bool CheckControlInput(Control ctrl, string strCaption, int iLength, bool blnNumber)
        {
            try
            {
                if (ctrl.GetType().ToString() == "System.Windows.Forms.TextBox")
                {
                    if (ctrl.Text.Trim() == "")
                    {
                        MsgBoxExclamation(strCaption + "不能为空，请输入" + strCaption);
                        ctrl.Focus();
                        ((TextBox)ctrl).SelectAll();
                        return false;
                    }
                    else if (iLength > 0 && ctrl.Text.Length != iLength)
                    {
                        MsgBoxExclamation("请输入" + iLength.ToString() + "位" + strCaption);
                        ctrl.Focus();
                        ((TextBox)ctrl).SelectAll();
                        return false;
                    }

                    if (blnNumber && !IsNumeric(ctrl.Text))
                    {
                        MsgBoxExclamation(strCaption + "必须为数字，请重新输入");
                        ctrl.Focus();
                        ((TextBox)ctrl).SelectAll();
                        return false;
                    }
                }
                else if (ctrl.GetType().ToString() == "System.Windows.Forms.ComboBox")
                {
                    if (ctrl.Text.Trim() == "")
                    {
                        MsgBoxExclamation(strCaption + "不能为空，请选择" + strCaption);
                        ctrl.Focus();
                        return false;
                    }
                }
                else
                {
                    if (ctrl.Text.Trim() == "")
                    {
                        MsgBoxExclamation(strCaption + "不能为空，请输入" + strCaption);
                        ctrl.Focus();
                        return false;
                    }
                }

                return true;
            }
            catch (System.Exception e)
            {
                MsgBoxException(e.Message, "GlobalFunction.CheckControlInput");
                return false;
            }
        }