windows窗口控件点击——CheckButton(一)

试图通过发送消息到一个button控件来模拟鼠标点击，遇到了点小麻烦，一直没有成功。该控件如图：

一开始，我是按照之前点击button控件的情况来处理，先是用FindWindowEx()查找到该控件的句柄，通过句柄和GetDlgCtrlID()函数来获取此button控件的ID，得到句柄和I控件D后，就可以对此控件发送消息了，代码如下：

hBtn = ::FindWindowEx(hWnd, NULL, NULL, _T("无边距打印"));                                      //通过控件的标题来查找句柄
IDn = ::GetDlgCtrlID(hBtn);

::SendNotifyMessage(hWnd, WM_COMMAND, MAKELONG(IDn, BN_CLICKED), (long)hBtn);

这段代码没有生效，但是当我把上面代码替换成该窗口中的其他Button控件，如OK按钮，却是可以成功点击到的。

难道”无边距打印“那个控件不是Button类型？但显然不对，因为在spy++中明显能看到这个控件是一个Button。我又试了PostMessage(),SendMessage()等各种消息发送函数，也试了MK_LBUTTON等鼠标点击消息，但都以失败告终。不过我想，这种前面有个打勾的框框和一般的button外观看起来就差异很大，也许Button会有不同的类型。于是我在VS的toolbox里面找了一下，找到了这种前面有个小框框的控件，原来它的名字叫做CheckBox。在MSDN搜索了一下，看到了这个：

MFC Library Reference

Button Styles

 

• BS_3STATE   Same as a check box, except that the box can be dimmed as well as checked. The dimmed state typically is used to show that a check box has been disabled.

• BS_AUTO3STATE   Same as a three-state check box, except that the box changes its state when the user selects it.

• BS_AUTOCHECKBOX   Same as a check box, except that a check mark appears in the check box when the user selects the box; the check mark disappears the next time the user selects the box.

• BS_AUTORADIOBUTTON   Same as a radio button, except that when the user selects it, the button automatically highlights itself and removes the selection from any other radio buttons with the same style in the same group.

• BS_BITMAP   Specifies that the button displays a bitmap.

• BS_BOTTOM   Places text at the bottom of the button rectangle.

• BS_CENTER   Centers text horizontally in the button rectangle.

• BS_CHECKBOX   Creates a small square that has text displayed to its right (unless this style is combined with the BS_LEFTTEXT style).

• BS_DEFPUSHBUTTON   Creates a button that has a heavy black border. The user can select this button by pressing the ENTER key. This style enables the user to quickly select the most likely option (the default option).

• BS_FLAT   Specifies that the button is two-dimensional; it does not use the default shading to create a 3-D image.

• BS_GROUPBOX   Creates a rectangle in which other buttons can be grouped. Any text associated with this style is displayed in the rectangle's upper-left corner.

• BS_ICON   Specifies that the button displays an icon.

• BS_LEFT   Left aligns the text in the button rectangle. However, if the button is a check box or radio button that does not have the BS_RIGHTBUTTON style, the text is left aligned on the right side of the check box or radio button.

• BS_LEFTTEXT   When combined with a radio-button or check-box style, the text appears on the left side of the radio button or check box.

• BS_MULTILINE   Wraps the button text to multiple lines if the text string is too long to fit on a single line in the button rectangle.

• BS_NOTIFY   Enables a button to send BN_DBLCLK, BN_KILLFOCUS, and BN_SETFOCUS notification messages to its parent window. Note that buttons send the BN_CLICKED notification message regardless of whether it has this style.

• BS_OWNERDRAW   Creates an owner-drawn button. The framework calls the DrawItem member function when a visual aspect of the button has changed. This style must be set when using theCBitmapButton class.

• BS_PUSHBUTTON   Creates a pushbutton that posts a WM_COMMAND message to the owner window when the user selects the button.

• BS_PUSHLIKE   Makes a button (such as a check box, three-state check box, or radio button) look and act like a push button. The button looks raised when it isn't pushed or checked, and sunken when it is pushed or checked.

• BS_RADIOBUTTON   Creates a small circle that has text displayed to its right (unless this style is combined with the BS_LEFTTEXT style). Radio buttons are usually used in groups of related, but mutually exclusive, choices.

• BS_RIGHT   Right aligns the text in the button rectangle. However, if the button is a check box or radio button that does not have the BS_RIGHTBUTTON style, the text is right aligned on the right side of the check box or radio button.

• BS_RIGHTBUTTON   Positions a radio button's circle or a check box's square on the right side of the button rectangle. Same as the BS_LEFTTEXT style.

• BS_TEXT   Specifies that the button displays text.

• BS_TOP   Places text at the top of the button rectangle.

• BS_USERBUTTON   Obsolete, but provided for compatibility with 16-bit versions of Windows. Win32-based applications should use BS_OWNERDRAW instead.

• BS_VCENTER   Places text in the middle (vertically) of the button rectangle
  原来Button是分这么多的style的，有了方向就好办了，很快，在MSDN找到一个叫ButtonSetCheck()的函数：

  LRESULT Button_SetCheck(  HWND hwndCtl,  int check);

• Check 参数说明如下：

• check
  Type: int
  The check state. This parameter can be one of the following values.
  ValueMeaning
  BST_CHECKED
  Sets the button state to checked.
  BST_INDETERMINATE
  Sets the button state to grayed, indicating an indeterminate state. Use this value only if the button has the BS_3STATE or BS_AUTO3STATE style.
  BST_UNCHECKED
  Sets the button state to cleared.
  接下来的就很简单了，只要一句Button_SetCheck(hBtn, BST_UNCHECKED); 就可以轻松把CheckBox前的小框框取消打勾。