四、关于Button的其他那些

一、SendMessage()函数

在Win32的消息处理机制中，分别有两种消息：一种是对于事件（如鼠标点击、移动等）发生产生的消息，被系统放入消息队列中，提交给相应程序的相应消息处理函数处理；另一种则是由程序本身发送给系统，来提交某个请求或获取信息。

例如，修改窗口标题SetWindowText()的API实际上也可以通过发送WM_SETTEXT消息来实现：

SendMessage(hWnd,WM_SETTEXT,0,(LPARAM)"OK");

二、单选按钮

创建单选按钮，只需要在CreateWindowEx()的时候将普通按钮的BS_PUSHBUTTON风格换成BS_RADIOBUTTON或者BS_AUTORADIOBUTTON。

BS_RADIOBUTTON：

CreateWindowEx(0,BUTTON,Radio1,WS_CHILD|WS_VISIBLE|BS_RADIOBUTTON,               4,4,150,32,hWnd,(HMENU)40001,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Radio2",WS_CHILD|WS_VISIBLE|BS_RADIOBUTTON,               4,40,150,32,hWnd,(HMENU)40002,g_hInstance,NULL);

这样就创建了两个单选按钮，但初始状态均为未选中状态，所以可以向其中一个单选按钮发送BM_SETCHECK消息来更改其选择/未选择状态：

SendMessage(GetDlgItem(hWnd,40001),BM_SETCHECK,BST_CHECKED,0);

其中BST_CHECKED表示设置为选中状态，设置未选中时使用BST_UNCHECKED。

为了保证两个单选按钮能够正常的进行切换，则需要在消息处理函数里作出相应处理，当单选按钮被点击时，与按钮性质一样会发出BN_CLICKED消息，而消息的wParam参数则记录了按钮ID。所以消息处理函数需要添加如下代码：

if(HIWORD(wParam)==BN_CLICKED){    if(LOWORD(wParam)==40001)    {        SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);        SendMessage(GetDlgItem(hWnd,IDC_BTN_RADIO2),BM_SETCHECK,BST_UNCHECKED,0);    }    else if(LOWORD(wParam)==40002)    {        SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);        SendMessage(GetDlgItem(hWnd,IDC_BTN_RADIO1),BM_SETCHECK,BST_UNCHECKED,0);    }}

BS_AUTORADIOBUTTON风格则是自动属性的单选按钮：

CreateWindowEx(0,"BUTTON","AutoRadio1",WS_CHILD|WS_VISIBLE|BS_AUTORADIOBUTTON|WS_GROUP,               4,4,150,32,hWnd,(HMENU)40001,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","AutoRadio2",WS_CHILD|WS_VISIBLE|BS_AUTORADIOBUTTON,               4,40,150,32,hWnd,(HMENU)40002,g_hInstance,NULL);SendMessage(GetDlgItem(hWnd,IDC_BTN_AUTORADIO1),BM_SETCHECK,BST_CHECKED,0);

由于是自动性质的单选按钮，故不再在消息处理函数中需要添加切换选中状态代码，由系统自动维护。

但是必须在创建时将第一个单选按钮的风格上加上WS_GROUP，表示以此单选按钮起ID连续的全部单选按钮均属于组。

三、复选按钮

不带自动属性的两状态复选按钮：

//创建：CreateWindowEx(0,"BUTTON","Check Box",WS_CHILD|WS_VISIBLE|BS_CHECKBOX,4,40,150,32,hWnd,(HMENU)40001,g_hInstance,NULL);

//消息处理函数中：if(LOWORD(wParam)==IDC_BTN_CHECK){    if(HIWORD(wParam)==BN_CLICKED)    {        int res=SendMessage((HWND)lParam,BM_GETCHECK,0,0);        if(res==BST_CHECKED)            SendMessage((HWND)lParam,BM_SETCHECK,BST_UNCHECKED,0);        else if(res==BST_UNCHECKED)            SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);    }}

带自动属性的两状态复选按钮：

CreateWindowEx(0,"BUTTON","Autocheck Box",WS_CHILD|WS_VISIBLE|BS_AUTOCHECKBOX,               4,40,150,32,hWnd,(HMENU)40002,g_hInstance,NULL);

不带自动属性的三状态复选按钮：

//创建：CreateWindowEx(0,"BUTTON","3 State",WS_CHILD|WS_VISIBLE|BS_3STATE,               4,40,150,32,hWnd,(HMENU)40003,g_hInstance,NULL);

//消息处理函数中：if(LOWORD(wParam)==IDC_BTN_3STATE){    if(HIWORD(wParam)==BN_CLICKED)       {        int res=SendMessage((HWND)lParam,BM_GETCHECK,0,0);        if(res==BST_CHECKED)            SendMessage((HWND)lParam,BM_SETCHECK,BST_INDETERMINATE,0);        else if(res==BST_INDETERMINATE)            SendMessage((HWND)lParam,BM_SETCHECK,BST_UNCHECKED,0);        else if(res==BST_UNCHECKED)            SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);    }}

带自动属性的三状态复选按钮：

CreateWindowEx(0,"BUTTON","Auto 3 State",WS_CHILD|WS_VISIBLE|BS_AUTO3STATE,               4,40,150,32,hWnd,(HMENU)40004,g_hInstance,NULL);

四、其他特殊按钮

分组框

CreateWindowEx(0,"BUTTON","Group Box",WS_CHILD|WS_VISIBLE|BS_GROUPBOX,               4,40,150,96,hWnd,(HMENU)40000,g_hInstance,NULL);

PushLike

CreateWindowEx(0,"BUTTON","PushLike",WS_CHILD|WS_VISIBLE|BS_AUTOCHECKBOX|BS_PUSHLIKE,               4,40,150,32,hWnd,(HMENU)40000,g_hInstance,NULL);

五、代码实例

创建简单Win32工程（Simple Win32）：

#include"stdafx.h"#include<stdio.h>#define IDC_BTN_PUSH4001#define IDC_BTN_DEFPUSH4002#define IDC_BTN_GROUP4003#define IDC_BTN_CHECK4004#define IDC_BTN_AUTOCHECK4005#define IDC_BTN_3STATE4006#define IDC_BTN_AUTO3STATE4007#define IDC_BTN_RADIO14008#define IDC_BTN_RADIO24009#define IDC_BTN_AUTORADIO14010#define IDC_BTN_AUTORADIO24011#define IDC_BTN_PUSHLIKE4012LPCSTR g_pszAppName="WinButton";LPCSTR g_pszMainWndClass="MAIN";HINSTANCE g_hInstance=NULL;void OnCreate(HWND hWnd,LPARAM lParam){int x=4,y=4;CreateWindowEx(0,"BUTTON","Push",WS_CHILD|WS_VISIBLE|BS_PUSHBUTTON,   x,y,150,32,hWnd,(HMENU)IDC_BTN_PUSH,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Default Push",WS_CHILD|WS_VISIBLE|BS_DEFPUSHBUTTON,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_DEFPUSH,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Group Box",WS_CHILD|WS_VISIBLE|BS_GROUPBOX,   x,y+=36,150,96,hWnd,(HMENU)IDC_BTN_GROUP,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Check Box",WS_CHILD|WS_VISIBLE|BS_CHECKBOX,   x,y+=100,150,32,hWnd,(HMENU)IDC_BTN_CHECK,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Autocheck Box",WS_CHILD|WS_VISIBLE|BS_AUTOCHECKBOX,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_AUTOCHECK,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","3 State",WS_CHILD|WS_VISIBLE|BS_3STATE,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_3STATE,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Auto 3 State",WS_CHILD|WS_VISIBLE|BS_AUTO3STATE,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_AUTO3STATE,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Radio1",WS_CHILD|WS_VISIBLE|BS_RADIOBUTTON|WS_GROUP,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_RADIO1,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","Radio2",WS_CHILD|WS_VISIBLE|BS_RADIOBUTTON,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_RADIO2,g_hInstance,NULL);SendMessage(GetDlgItem(hWnd,IDC_BTN_RADIO1),BM_SETCHECK,BST_CHECKED,0);CreateWindowEx(0,"BUTTON","AutoRadio1",WS_CHILD|WS_VISIBLE|BS_AUTORADIOBUTTON|WS_GROUP,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_AUTORADIO1,g_hInstance,NULL);CreateWindowEx(0,"BUTTON","AutoRadio2",WS_CHILD|WS_VISIBLE|BS_AUTORADIOBUTTON,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_AUTORADIO2,g_hInstance,NULL);SendMessage(GetDlgItem(hWnd,IDC_BTN_AUTORADIO1),BM_SETCHECK,BST_CHECKED,0);CreateWindowEx(0,"BUTTON","PushLike",WS_CHILD|WS_VISIBLE|BS_AUTOCHECKBOX|BS_PUSHLIKE,   x,y+=36,150,32,hWnd,(HMENU)IDC_BTN_PUSHLIKE,g_hInstance,NULL);}void OnCommand(HWND hWnd,WPARAM wParam,LPARAM lParam){if(LOWORD(wParam)==IDC_BTN_DEFPUSH||LOWORD(wParam)==IDC_BTN_PUSH){if(HIWORD(wParam)==BN_CLICKED){CHAR szText[256]={0};GetWindowText((HWND)lParam,szText,sizeof(szText)/sizeof(szText[0]));MessageBox(hWnd,szText,"Push",MB_OK);}}if(LOWORD(wParam)==IDC_BTN_CHECK){if(HIWORD(wParam)==BN_CLICKED){int res=SendMessage((HWND)lParam,BM_GETCHECK,0,0);if(res==BST_CHECKED)SendMessage((HWND)lParam,BM_SETCHECK,BST_UNCHECKED,0);else if(res==BST_UNCHECKED)SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);}}if(LOWORD(wParam)==IDC_BTN_3STATE){if(HIWORD(wParam)==BN_CLICKED){int res=SendMessage((HWND)lParam,BM_GETCHECK,0,0);if(res==BST_CHECKED)SendMessage((HWND)lParam,BM_SETCHECK,BST_INDETERMINATE,0);else if(res==BST_INDETERMINATE)SendMessage((HWND)lParam,BM_SETCHECK,BST_UNCHECKED,0);else if(res==BST_UNCHECKED)SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);}}if(LOWORD(wParam)==IDC_BTN_RADIO1){if(HIWORD(wParam)==BN_CLICKED){SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);SendMessage(GetDlgItem(hWnd,IDC_BTN_RADIO2),BM_SETCHECK,BST_UNCHECKED,0);}}if(LOWORD(wParam)==IDC_BTN_RADIO2){if(HIWORD(wParam)==BN_CLICKED){SendMessage((HWND)lParam,BM_SETCHECK,BST_CHECKED,0);SendMessage(GetDlgItem(hWnd,IDC_BTN_RADIO1),BM_SETCHECK,BST_UNCHECKED,0);}}}LRESULT CALLBACK MainWndProc(HWND hWnd,UINT uMsg,WPARAM wParam,LPARAM lParam){switch(uMsg){case WM_COMMAND:OnCommand(hWnd,wParam,lParam);break;case WM_CREATE:OnCreate(hWnd,lParam);break;case WM_DESTROY:PostQuitMessage(0);return 0;}return DefWindowProc(hWnd,uMsg,wParam,lParam);}ATOM InitApplication(HINSTANCE hInstance){WNDCLASSEX wcex={0};wcex.cbSize=sizeof(wcex);wcex.style=CS_HREDRAW|CS_VREDRAW;wcex.lpfnWndProc=MainWndProc;wcex.cbClsExtra=0;wcex.cbWndExtra=0;wcex.hInstance=hInstance;wcex.hIcon=LoadIcon(NULL,IDI_APPLICATION);wcex.hIconSm=LoadIcon(NULL,IDI_WARNING);wcex.hCursor=LoadCursor(NULL,IDC_ARROW);wcex.hbrBackground=GetSysColorBrush(COLOR_3DFACE);wcex.lpszMenuName=NULL;wcex.lpszClassName=g_pszMainWndClass;return RegisterClassEx(&wcex);}BOOL InitInstance(HINSTANCE hInstance,int nCmdShow){g_hInstance=hInstance;HWND hWnd=CreateWindowEx(WS_EX_CLIENTEDGE,g_pszMainWndClass,g_pszAppName,WS_OVERLAPPEDWINDOW, CW_USEDEFAULT,CW_USEDEFAULT,170,15*36,NULL,NULL, hInstance,NULL);if(!hWnd) return 0;ShowWindow(hWnd,nCmdShow);UpdateWindow(hWnd);return 1;}int APIENTRY WinMain(HINSTANCE hInstance,                     HINSTANCE hPrevInstance,                     LPSTR     lpCmdLine,                     int       nCmdShow){if(!hPrevInstance)if(!InitApplication(hInstance))return 0;if(!InitInstance(hInstance,nCmdShow)) return 0;MSG msg={0};while(GetMessage(&msg,NULL,0,0)){TranslateMessage(&msg);DispatchMessage(&msg);}return 0;}