1.
可以添加
但不可能像AddItem一样
因为VB不知道你添加了项目，没有加入List集合
LB_ADDSTRING
An application sends an LB_ADDSTRING message to add a string to a list box. If the list box does not have the LBS_SORT style, the string is added to the end of the list. Otherwise, the string is inserted into the list and the list is sorted. LB_ADDSTRING
wParam = 0; // not used; must be zero
lParam = (LPARAM) (LPCTSTR) lpsz; // address of string to add
Parameters
lpsz
Value of lParam. Pointer to the null-terminated string that is to be added.
If you create the list box with an owner-drawn style but without the LBS_HASSTRINGS style, the value of the lpsz parameter is stored as item data instead of the string it would otherwise point to. You can send the LB_GETITEMDATA and LB_SETITEMDATA messages to retrieve or modify the item data. Return Values
The return value is the zero-based index of the string in the list box. If an error occurs, the return value is LB_ERR. If there is insufficient space to store the new string, the return value is LB_ERRSPACE. Res
If you create an owner-drawn list box with the LBS_SORT style but not the LBS_HASSTRINGS style, the system sends the WM_COMPAREITEM message one or more times to the owner of the list box to place the new item properly in the list box. QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.2.
WM_HSCROLL
The WM_HSCROLL message is sent to a window when a scroll event occurs in the window's standard horizontal scroll bar. This message is also sent to the owner of a horizontal scroll bar control when a scroll event occurs in the control. WM_HSCROLL
nScrollCode = (int) LOWORD(wParam); // scroll bar value
nPos = (short int) HIWORD(wParam); // scroll box position
hwndScrollBar = (HWND) lParam; // handle to scroll bar
Parameters
nScrollCode
Value of the low-order word of wParam. Specifies a scroll bar value that indicates the user's scrolling request. This parameter can be one of the following values: Value Meaning
SB_ENDSCROLL Ends scroll.
SB_LEFT Scrolls to the upper left.
SB_RIGHT Scrolls to the lower right.
SB_LINELEFT Scrolls left by one unit.
SB_LINERIGHT Scrolls right by one unit.
SB_PAGELEFT Scrolls left by the width of the window.
SB_PAGERIGHT Scrolls right by the width of the window.
SB_THUMBPOSITION The user has dragged the scroll box (thumb) and released the mouse button. The nPos parameter indicates the position of the scroll box at the end of the drag operation.
SB_THUMBTRACK The user is dragging the scroll box. This message is sent repeatedly until the user releases the mouse button. The nPos parameter indicates the position that the scroll box has been dragged to.
nPos
Value of the high-order word of wParam. Specifies the current position of the scroll box if the nScrollCode parameter is SB_THUMBPOSITION or SB_THUMBTRACK; otherwise, nPos is not used.
hwndScrollBar
Value of lParam. If the message is sent by a scroll bar, then hwndScrollBar is the handle to the scroll bar control. If the message is not sent by a scroll bar, hwndScrollBar is NULL.
Return Values
If an application processes this message, it should return zero. Res
The SB_THUMBTRACK notification message is typically used by applications that provide feedback as the user drags the scroll box. If an application scrolls the content of the window, it must also reset the position of the scroll box by using the SetScrollPos function. Note that the WM_HSCROLL message carries only 16 bits of scroll box position data. Thus, applications that rely solely on WM_HSCROLL (and WM_VSCROLL) for scroll position data have a practical maximum position value of 65,535. However, because the SetScrollInfo, SetScrollPos, SetScrollRange, GetScrollInfo, GetScrollPos, and GetScrollRange functions support 32-bit scroll bar position data, there is a way to circumvent the 16-bit barrier of the WM_HSCROLL and WM_VSCROLL messages. See GetScrollInfo for a description of the technique. QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
可以添加
但不可能像AddItem一样
因为VB不知道你添加了项目，没有加入List集合
LB_ADDSTRING
An application sends an LB_ADDSTRING message to add a string to a list box. If the list box does not have the LBS_SORT style, the string is added to the end of the list. Otherwise, the string is inserted into the list and the list is sorted. LB_ADDSTRING
wParam = 0; // not used; must be zero
lParam = (LPARAM) (LPCTSTR) lpsz; // address of string to add
Parameters
lpsz
Value of lParam. Pointer to the null-terminated string that is to be added.
If you create the list box with an owner-drawn style but without the LBS_HASSTRINGS style, the value of the lpsz parameter is stored as item data instead of the string it would otherwise point to. You can send the LB_GETITEMDATA and LB_SETITEMDATA messages to retrieve or modify the item data. Return Values
The return value is the zero-based index of the string in the list box. If an error occurs, the return value is LB_ERR. If there is insufficient space to store the new string, the return value is LB_ERRSPACE. Res
If you create an owner-drawn list box with the LBS_SORT style but not the LBS_HASSTRINGS style, the system sends the WM_COMPAREITEM message one or more times to the owner of the list box to place the new item properly in the list box. QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.2.
WM_HSCROLL
The WM_HSCROLL message is sent to a window when a scroll event occurs in the window's standard horizontal scroll bar. This message is also sent to the owner of a horizontal scroll bar control when a scroll event occurs in the control. WM_HSCROLL
nScrollCode = (int) LOWORD(wParam); // scroll bar value
nPos = (short int) HIWORD(wParam); // scroll box position
hwndScrollBar = (HWND) lParam; // handle to scroll bar
Parameters
nScrollCode
Value of the low-order word of wParam. Specifies a scroll bar value that indicates the user's scrolling request. This parameter can be one of the following values: Value Meaning
SB_ENDSCROLL Ends scroll.
SB_LEFT Scrolls to the upper left.
SB_RIGHT Scrolls to the lower right.
SB_LINELEFT Scrolls left by one unit.
SB_LINERIGHT Scrolls right by one unit.
SB_PAGELEFT Scrolls left by the width of the window.
SB_PAGERIGHT Scrolls right by the width of the window.
SB_THUMBPOSITION The user has dragged the scroll box (thumb) and released the mouse button. The nPos parameter indicates the position of the scroll box at the end of the drag operation.
SB_THUMBTRACK The user is dragging the scroll box. This message is sent repeatedly until the user releases the mouse button. The nPos parameter indicates the position that the scroll box has been dragged to.
nPos
Value of the high-order word of wParam. Specifies the current position of the scroll box if the nScrollCode parameter is SB_THUMBPOSITION or SB_THUMBTRACK; otherwise, nPos is not used.
hwndScrollBar
Value of lParam. If the message is sent by a scroll bar, then hwndScrollBar is the handle to the scroll bar control. If the message is not sent by a scroll bar, hwndScrollBar is NULL.
Return Values
If an application processes this message, it should return zero. Res
The SB_THUMBTRACK notification message is typically used by applications that provide feedback as the user drags the scroll box. If an application scrolls the content of the window, it must also reset the position of the scroll box by using the SetScrollPos function. Note that the WM_HSCROLL message carries only 16 bits of scroll box position data. Thus, applications that rely solely on WM_HSCROLL (and WM_VSCROLL) for scroll position data have a practical maximum position value of 65,535. However, because the SetScrollInfo, SetScrollPos, SetScrollRange, GetScrollInfo, GetScrollPos, and GetScrollRange functions support 32-bit scroll bar position data, there is a way to circumvent the 16-bit barrier of the WM_HSCROLL and WM_VSCROLL messages. See GetScrollInfo for a description of the technique. QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
解决方案 »
免费领取超大流量手机卡，每月29元包185G流量+100分钟通话, 中国电信官方发货