DateTimePicker UpDown溢出

Question

我在我的DateTimePicker表单中添加了C#。我使用Time格式和ShowUpDown = true。当我使用上/下按钮时，小时、分钟或秒增加/减少。当秒溢出(从59到0或0到59 )时，我想增加分钟。有办法吗？

它现在是如何运作的：

• TimerPicker = 00:01:59→按UpKey on second→TimerPicker = 00:01:00
• TimerPicker = 05:00:38→按DownKey on→TimerPicker = 05:59:38

我希望它能起作用：

• TimerPicker = 00:01:59→press UpKey on second→TimerPicker =UpKey= 05:00:38→press DownKey on→TimerPicker = 04:59:38

编辑:下面是与DateTimePicker相关的代码：

DataGraph.Designer.cs：

this.TimePerDivisionPicker = new System.Windows.Forms.DateTimePicker();
// 
// TimePerDivisionPicker
// 
this.TimePerDivisionPicker.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
this.TimePerDivisionPicker.CustomFormat = "";
this.TimePerDivisionPicker.Format = System.Windows.Forms.DateTimePickerFormat.Time;
this.TimePerDivisionPicker.ImeMode = System.Windows.Forms.ImeMode.On;
this.TimePerDivisionPicker.Location = new System.Drawing.Point(83, 16);
this.TimePerDivisionPicker.Name = "TimePerDivisionPicker";
this.TimePerDivisionPicker.RightToLeft = System.Windows.Forms.RightToLeft.No;
this.TimePerDivisionPicker.ShowUpDown = true;
this.TimePerDivisionPicker.Size = new System.Drawing.Size(85, 20);
this.TimePerDivisionPicker.TabIndex = 4;
this.TimePerDivisionPicker.Value = new System.DateTime(2020, 3, 2, 0, 1, 0, 0);
this.TimePerDivisionPicker.ValueChanged += new System.EventHandler(this.TimePerDivisionPicker_ValueChanged);

DataGraph.cs：

private void TimePerDivisionPicker_ValueChanged(object sender, EventArgs e)
{
    String[] temp = TimePerDivisionPicker.Text.Split(':');
    UInt16 tempHours = Convert.ToUInt16(temp[0]);
    UInt16 tempMinutes = Convert.ToUInt16(temp[1]);
    UInt16 tempSecondes = Convert.ToUInt16(temp[2]);
    TimePerDivision = Convert.ToUInt32(tempHours * 3600 + tempMinutes * 60 + tempSecondes);
}

Answer 1

您必须处理上/下键，并单击向上/向下箭头。然后比较旧的时间和新的时间，并增加小时或分钟。

如果您的日期时间超出范围(最小/最大DateTime)，可能会出现问题。

这不是最好的解决办法，但有效。

public class MyTimePicker : DateTimePicker
{
    private Arrow _pressedArrow;
    private DateTime? _oldValue;

    public MyTimePicker()
    {
        Format = DateTimePickerFormat.Time;
        ShowUpDown = true;
    }

    protected override void OnValueChanged(EventArgs eventargs)
    {
        base.OnValueChanged(eventargs);

        if (!_oldValue.HasValue)
        {
            return;
        }
        var diff = Value - _oldValue.Value;
        _oldValue = null;

        if (_pressedArrow == Arrow.Up)
        {
            if (diff.Minutes < 0)
            {
                Value = Value.AddHours(1);
            }
            else if (diff.Seconds < 0)
            {
                Value = Value.AddMinutes(1);
            }
        }
        else if (_pressedArrow == Arrow.Down)
        {
            if (diff.Minutes > 0)
            {
                Value = Value.AddHours(-1);
            }
            else if (diff.Seconds > 0)
            {
                Value = Value.AddMinutes(-1);
            }
        }
    }

    protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
    {
        switch (keyData)
        {
            case Keys.Up: HandleArrow(Arrow.Up); break;
            case Keys.Down: HandleArrow(Arrow.Down); break;
            default: break;
        }
        return base.ProcessCmdKey(ref msg, keyData);
    }

    protected override void WndProc(ref Message m)
    {
        if (m.Msg == 0x204e || m.Msg == 0x4e)
        {
            NMHDR nfy = (NMHDR)Marshal.PtrToStructure(m.LParam, typeof(NMHDR));
            if (nfy.code == -722)
            {
                NMUPDOWN ud = (NMUPDOWN)Marshal.PtrToStructure(m.LParam, typeof(NMUPDOWN));
                HandleArrow(ud.delta < 0 ? Arrow.Down : Arrow.Up);
            }
        }
        base.WndProc(ref m);
    }

    private bool HandleArrow(Arrow arrow)
    {
        _pressedArrow = arrow;
        _oldValue = Value;
        return false;
    }

    private enum Arrow
    {
        Up,
        Down,
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct NMHDR
    {
        public IntPtr hwndFrom;
        public IntPtr idFrom;
        public int code;
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct NMUPDOWN
    {
        public NMHDR hdr;
        public int pos;
        public int delta;
    }
}