文本输出方法与字体的设置

学习目的

掌握获取字体句柄的两种方法;调用CreateFont函数创建自定义字体; 调用SetTextColor和SetBkColor函数设置字体的颜色和背景色; 掌握文本输出的过程(获取字体信息, 格式化文本, 输出文本).

 

1. 掌握获取字体句柄的方法：

HFONT hF; //定义字体句柄变量hF

hF=GetStockObject(); //获得系统字体句柄

SelectObject(hdc,hF); //将字体选入设备环境

 

2. CreateFont函数创建自定义字体

HFont = CreateFont(

int nHeight, // height of font

int nWidth, // average character width

int nEscapement, // angle of escapement

int nOrientation, // base-line orientation angle

int fnWeight, // font weight

DWORD fdwItalic, // italic attribute option

DWORD fdwUnderline, // underline attribute option

DWORD fdwStrikeOut, // strikeout attribute option

DWORD fdwCharSet, // character set identifier

DWORD fdwOutputPrecision, // output precision

DWORD fdwClipPrecision, // clipping precision

DWORD fdwQuality, // output quality

DWORD fdwPitchAndFamily, // pitch and family

LPCTSTR lpszFace // typeface name

);

3.设置字体的颜色和背景色

SetTextColor（hdc,crColor）; //设置字体颜色

SetBkColor(hdc,crColor); //设置背景色色

4. 掌握文本输出的过程

（1）获取字体信息

GetTextMetrics（hdc,&tm）；

（2） 格式化文本

用GetTextExtentPoint32()确定后续文本的坐标,然后根据当前字体信息确定换行后的坐标。

（3） 输出文本

使用TextOut或者DrawText输出文本：

BOOL TextOut(

  HDC
										hdc,           // handle to DC

  int
										nXStart,       // x-coordinate of starting position

  int
										nYStart,       // y-coordinate of starting position

  LPCTSTR
										lpString,  // character string

									 int
									cbString       // number of characters

);
								

int DrawText(  

HDC hDC,          // handle to DC

  LPCTSTR lpString, // text to draw  
									

int nCount,       // text length
									

  LPRECT lpRect,    // formatting dimensions
									

  UINT uFormat
									 // text-drawing options
									

);

5.编写程序: 在窗口上设计一行文字, 要求文字能在窗口中向左滚动显示, 而且每显示一轮, 改变一次颜色和字体.

程序主要代码如下：

static int Flag=0;

int X=0;

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)

{

    int wmId, wmEvent;

    PAINTSTRUCT ps;

    HDC hDC;

    RECT clientRect;

    //TCHAR szHello[MAX_LOADSTRING];

    //LoadString(hInst, IDS_HELLO, szHello, MAX_LOADSTRING);

    HFONT hF;            

    TEXTMETRIC tm;    

    char text[]="Windows 程序设计实验三";        //输出的字符串.

    char chFont[7];                                //定义包含字体的字符串.

    int xOrg,yOrg,Y=0,nCharlen=strlen(text);

    switch (message)

    {

        case WM_CREATE:

        SetTimer(hWnd,1,50,NULL);        //设定定时器.每0.2秒发出WM_TIMER消息.

        break;

        case WM_COMMAND:

            wmId = LOWORD(wParam);

            wmEvent = HIWORD(wParam);

            // Parse the menu selections:

            switch (wmId)

            {

                case IDM_ABOUT:

                 DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);

                 break;

                case IDM_EXIT:

                 DestroyWindow(hWnd);

                 break;

                default:

                 return DefWindowProc(hWnd, message, wParam, lParam);

            }

            break;

        case WM_PAINT:

            hDC = BeginPaint(hWnd, &ps);

            GetClientRect(hWnd,&clientRect);

            xOrg=(clientRect.left+clientRect.right)/2;

            yOrg=(clientRect.top+clientRect.bottom)/2;

 

            SetViewportOrgEx(hDC,0,yOrg,NULL);

            // TODO: Add any drawing code here...

 

            if(Flag%4==0)    //设置字体颜色.

            {

                SetTextColor(hDC,RGB(255,0,0));

                strcpy(chFont,"楷体");

            }

            else if(Flag%4==1)

            {

                SetTextColor(hDC,RGB(0,255,0));

                strcpy(chFont,"宋体");

            }

            else if(Flag%4==2)

            {

                SetTextColor(hDC,RGB(0,0,255));

                strcpy(chFont,"仿宋体");

            }

            else if(Flag%4==3)

            {

                SetTextColor(hDC,RGB(255,255,0));

                strcpy(chFont,"黑体");

            }

            hF=CreateFont(            //获得字体句柄.

                100,                //字体高度

                0,                    //系统自动调整宽度.

                0,                    //文本水平

                0,                    //字体倾斜度为0

                400,                //字体粗度.400为正常.

                0,                    //字体不倾斜.

                0,                    //无下划线.

                0,                    //无中划线.

                GB2312_CHARSET,        //字符集

                OUT_DEFAULT_PRECIS,    //默认输出精度.

                CLIP_DEFAULT_PRECIS,//默认裁剪精度

                DEFAULT_QUALITY,    //默认输出质量.

                DEFAULT_PITCH|FF_DONTCARE,//默认间距

                chFont);         //字体名称.

 

            SelectObject(hDC,hF);    //选入字体.

            GetTextMetrics(hDC,&tm);    //得到字体的信息.

            TextOut(hDC,X,Y-tm.tmHeight/2,&text[0],nCharlen); //输出.

 

            X-=10;

            if(X+tm.tmAveCharWidth*nCharlen<0){

                Flag++;

                if(Flag==4)

                    Flag=0;

                X=clientRect.right;

            }

 

            DeleteObject(hF);    //删除字体.

            EndPaint(hWnd, &ps);

            break;

        case WM_TIMER:

        InvalidateRect(hWnd,NULL,1);    //刷新用户区.

        break;

        case WM_DESTROY:

            PostQuitMessage(0);

            break;

        default:

            return DefWindowProc(hWnd, message, wParam, lParam);

}

return 0;

}

编译并调试程序，

 

滚动文字运行结果如下图：

 

本次学习的涉及文本输出，需要注意Windows字符类型！