constants BackgroundPartEnum
The BackgroundPartEnum type indicates parts in the control. Use the Background property to specify a background color or a visual appearance for specific parts in the control. A Color expression that indicates the background color for a specified part. The last 7 bits in the high significant byte of the color to indicates the identifier of the skin being used. Use the Add method to add new skins to the control. If you need to remove the skin appearance from a part of the control you need to reset the last 7 bits in the high significant byte of the color being applied to the background's part

If you refer a part of the scroll bar please notice the following:  


NameValueDescription
exExpandButtonUp0 Specifies the visual appearance for the expand button, when it is up. 
exExpandButtonDown1 Specifies the visual appearance for the expand button, when it is down.
exExpandBarButtonUp2 Specifies the visual appearance for the button in the control's expand bar, when it is up.
exExpandBarButtonDown3 Specifies the visual appearance for the button in the control's expand bar, when it is down.
exDropDownButtonUp4 Specifies the visual appearance for the drop down button, when it is up.
exDropDownButtonDown5 Specifies the visual appearance for the drop down button, when it is down.
exButtonUp6 Specifies the visual appearance for the button inside the editor, when it is up. Use the AddButton method to add new buttons to the editor.
exButtonDown7 Specifies the visual appearance for the button inside the editor, when it is down.
exDateHeader8 Specifies the visual appearance for the header in a calendar control.
exDateTodayUp9 Specifies the visual appearance for the today button in a calendar control, when it is up.
exDateTodayDown10 Specifies the visual appearance for the today button in a calendar control, when it is down.
exDateScrollThumb11 Specifies the visual appearance for the scrolling thumb in a calendar control.
exDateScrollRange12 Specifies the visual appearance for the scrolling range in a calendar control.
exDateSeparatorBar13 Specifies the visual appearance for the separator bar in a calendar control.
exDateSelect14 Specifies the visual appearance for the selected date in a calendar control.
exSliderRange15 Specifies the visual appearance for the slider's bar.
exSliderThumb16 Specifies the visual appearance for the thumb of the slider.
exShowFocusRect19 exShowFocusRect. Specifies the visual appearance to display the node with the focus.
exSpinUpButtonUp22 Specifies the visual appearance for the up spin button when it is not pressed.
exSpinUpButtonDown23 Specifies the visual appearance for the up spin button when it is pressed.
exSpinDownButtonUp24 Specifies the visual appearance for the down spin button when it is not pressed.
exSpinDownButtonDown25 Specifies the visual appearance for the down spin button when it is pressed.
exCollapseButtonUp62 exCollapseButtonUp. Specifies the visual appearance for the expand button, when it is up, and the node is collapsed.
exFooterFilterBarButton63 exFooterFilterBarButton. Specifies the background color for the closing button in the filter bar.
exToolTipAppearance64 Indicates the visual appearance of the borders of the tooltips. Use the ToolTipPopDelay property specifies the period in ms of time the ToolTip remains visible if the mouse pointer is stationary within a control. Use the ToolTipWidth property to specify the width of the tooltip window. The ToolTipDelay property specifies the time in ms that passes before the ToolTip appears. Use the ShowToolTip method to display a custom tooltip.
exToolTipBackColor65 Specifies the tooltip's background color.
exToolTipForeColor66 Specifies the tooltip's foreground color.
exVSUp256 The up button in normal state.
exVSUpP257 The up button when it is pressed.
exVSUpD258 The up button when it is disabled.
exVSUpH259 The up button when the cursor hovers it.
exVSThumb260 The thumb part (exThumbPart) in normal state.
exVSThumbP261 The thumb part (exThumbPart) when it is pressed.
exVSThumbD262 The thumb part (exThumbPart) when it is disabled.
exVSThumbH263 The thumb part (exThumbPart) when cursor hovers it.
exVSDown264 The down button in normal state.
exVSDownP265 The down button when it is pressed.
exVSDownD266 The down button when it is disabled.
exVSDownH267 The down button when the cursor hovers it.
exVSLower268 The lower part ( exLowerBackPart ) in normal state.
exVSLowerP269 The lower part ( exLowerBackPart ) when it is pressed.
exVSLowerD270 The lower part ( exLowerBackPart ) when it is disabled.
exVSLowerH271 The lower part ( exLowerBackPart ) when the cursor hovers it.
exVSUpper272 The upper part ( exUpperBackPart ) in normal state.
exVSUpperP273 The upper part ( exUpperBackPart ) when it is pressed.
exVSUpperD274 The upper part ( exUpperBackPart ) when it is disabled.
exVSUpperH275 The upper part ( exUpperBackPart ) when the cursor hovers it.
exVSBack276 The background part ( exLowerBackPart and exUpperBackPart ) in normal state.
exVSBackP277 The background part ( exLowerBackPart and exUpperBackPart ) when it is pressed.
exVSBackD278 The background part ( exLowerBackPart and exUpperBackPart ) when it is disabled.
exVSBackH279 The background part ( exLowerBackPart and exUpperBackPart ) when the cursor hovers it.
exHSLeft384 The left button in normal state.
exHSLeftP385 The left button when it is pressed.
exHSLeftD386 The left button when it is disabled.
exHSLeftH387 The left button when the cursor hovers it.
exHSThumb388 The thumb part (exThumbPart) in normal state.
exHSThumbP389 The thumb part (exThumbPart) when it is pressed.
exHSThumbD390 The thumb part (exThumbPart) when it is disabled.
exHSThumbH391 The thumb part (exThumbPart) when the cursor hovers it.
exHSRight392 The right button in normal state.
exHSRightP393 The right button when it is pressed.
exHSRightD394 The right button when it is disabled.
exHSRightH395 The right button when the cursor hovers it.
exHSLower396 The lower part (exLowerBackPart) in normal state.
exHSLowerP397 The lower part (exLowerBackPart) when it is pressed.
exHSLowerD398 The lower part (exLowerBackPart) when it is disabled.
exHSLowerH399 The lower part (exLowerBackPart) when the cursor hovers it.
exHSUpper400 The upper part (exUpperBackPart) in normal state.
exHSUpperP401 The upper part (exUpperBackPart) when it is pressed.
exHSUpperD402 The upper part (exUpperBackPart) when it is disabled.
exHSUpperH403 The upper part (exUpperBackPart) when the cursor hovers it.
exHSBack404 The background part (exLowerBackPart and exUpperBackPart) in normal state.
exHSBackP405 The background part (exLowerBackPart and exUpperBackPart) when it is pressed.
exHSBackD406 The background part (exLowerBackPart and exUpperBackPart) when it is disabled.
exHSBackH407 The background part (exLowerBackPart and exUpperBackPart) when the cursor hovers it.
exSBtn324 All button parts ( L1-L5, LButton, exThumbPart, RButton, R1-R6 ), in normal state.
exSBtnP325 All button parts ( L1-L5, LButton, exThumbPart, RButton, R1-R6 ), when it is pressed.
exSBtnD326 All button parts ( L1-L5, LButton, exThumbPart, RButton, R1-R6 ), when it is disabled.
exSBtnH327 All button parts ( L1-L5, LButton, exThumbPart, RButton, R1-R6 ), when the cursor hovers it .
exScrollHoverAll500 Enables or disables the hover-all feature. By default (Background(exScrollHoverAll) = 0), the left/top, right/bottom and thumb parts of the control' scrollbars are displayed in hover state while the cursor hovers any part of the scroll bar (hover-all feature). The hover-all feature is available on Windows 11 or greater, if only left/top, right/bottom, thumb, lower and upper-background parts of the scrollbar are visible, no custom visual-appearance is applied to any visible part. The hover-all feature is always on If Background(exScrollHoverAll) = -1. The Background(exScrollHoverAll) = 1 disables the hover-all feature.
exVSThumbExt503 exVSThumbExt. The thumb-extension part in normal state.
exVSThumbExtP504 exVSThumbExtP. The thumb-extension part when it is pressed.
exVSThumbExtD505 exVSThumbExtD. The thumb-extension part when it is disabled.
exVSThumbExtH506 exVSThumbExtH. The thumb-extension when the cursor hovers it.
exHSThumbExt507 exHSThumbExt. The thumb-extension in normal state.
exHSThumbExtP508 exHSThumbExtP. The thumb-extension when it is pressed.
exHSThumbExtD509 exHSThumbExtD. The thumb-extension when it is disabled.
exHSThumbExtH510 exHSThumbExtH. The thumb-extension when the cursor hovers it.
exScrollSizeGrip511 Specifies the visual appearance of the control's size grip, when both scroll bars are displayed.