完整的delphi程序设计教程课后习题答案

239页1题小时钟procedure TForm1.Timer1Timer(Sender: TObject);varxt,yt:integer;h,m,s,ms:word;begindecodetime(time,h,m,s,ms);xt:=paintbox1.clientwidth div 2;yt:=paintbox1.clientheight div 2;paintbox1.refresh;paintbox1.canvas.moveto(xt,yt);paintbox1.canvas.pen.width:=3;paintbox1.canvas.lineto(xt+round(sin((60*h+m)/(12*60)*2*pi)*100), yt-round(cos((60*h+m)/(12*60)*2*pi)*100));paintbox1.canvas.moveto(xt,yt);paintbox1.canvas.pen.width:=2;paintbox1.canvas.lineto(xt+round(sin(m/60*2*pi)*140),yt-round(cos(m/60*2*pi)*140));paintbox1.canvas.moveto(xt,yt);paintbox1.canvas.pen.width:=1;paintbox1.canvas.lineto(xt+round(sin(s/60*2*pi)*180),yt-round(cos(s/60*2*pi)*180));end;end.239页3题求两点间的距离procedure TForm1.Button1Click(Sender: TObject);beginpaintbox1.Refresh;formpaint(sender);end;procedure TForm1.FormPaint(Sender: TObject);varxt,yt:integer;ax,ay,bx,by:integer;beginxt:=paintbox1.ClientWidth div 2;yt:=paintbox1.Clientheight div 2;paintbox1.canvas.MoveTo(xt,0);paintbox1.canvas.lineTo(xt,2*yt);paintbox1.canvas.MoveTo(0,yt);paintbox1.canvas.lineTo(2*xt,yt);ax:=strtoint(edit1.text);ay:=strtoint(edit2.text);bx:=strtoint(edit3.text);by:=strtoint(edit4.text);edit5.Text:=floattostr(sqrt((ax-bx)*(ax-bx)+(ay-by)*(ay-by))); paintbox1.canvas.MoveTo(xt+ax*10,yt-ay*10);paintbox1.canvas.lineTo(xt+bx*10,yt-by*10);end;end.226页5题输入学生成绩varForm1: TForm1;typestudentrecord=recordxh,xm:string[6];xb:boolean;yy,sx,dz:integer;end;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);var t:studentrecord;f:file of studentrecord;size:integer;begint.xh:=edit1.Text;t.xm:=edit2.Text;t.sx:=strtoint(edit3.Text);t.yy:=strtoint(edit4.Text);t.dz:=strtoint(edit5.Text);if radiobutton1.Checked thent.xb:=trueelset.xb:=false;assignfile(f,'c:\my documents\stu.dat');if fileexists('c:\my documents\stu.dat') thenreset(f)elserewrite(f);size:=filesize(f);seek(f,size);write(f,t);closefile(f);edit1.Text:='';edit2.Text:='';edit3.Text:='';edit4.Text:='';edit5.Text:='';end;procedure TForm1.Button2Click(Sender: TObject); beginclose;end;end.226页8题保存获得奖学金者varForm1: TForm1;typestudentrecord=recordxh,xm:string[6];xb:boolean;yy,sx,dz:integer;end;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject); var t:studentrecord;f,f1:file of studentrecord;p1,p2:boolean;beginassignfile(f,'c:\my documents\stu.dat');reset(f);assignfile(f1,'c:\my documents\stu1.dat');rewrite(f1);while not eof(f) dobeginread(f,t);p1:=(t.sx>=85)and(t.yy>=85)and(t.dz>=85);p2:=t.sx+t.yy+t.dz>=270;if p1 or p2 thenwrite(f1,t);end;closefile(f);closefile(f1);end;procedure TForm1.FormCreate(Sender: TObject);var t:studentrecord;f:file of studentrecord;xingbie:string;beginassignfile(f,'c:\my documents\stu1.dat');reset(f);while not eof(f) dobeginread(f,t);if t.xb thenxingbie:='男'elsexingbie:='女';listbox1.Items.Add(t.xh+' '+t.xm+' '+xingbie+' '+inttostr(t.sx)+ ' '+inttostr(t.yy)+' '+inttostr(t.dz));end;closefile(f);end;procedure TForm1.Button2Click(Sender: TObject);beginclose;end;end.166页22题素数procedure TForm1.Button1Click(Sender: TObject);typesushuset=set of byte;varsushu:sushuset;i,j,n,m,k:longword;s,s0:string;beginn:=strtoint(edit1.text);m:=strtoint(edit2.text);if n mod 2=0 then n:=n+1;k:=m-n;if k>255 thenshowmessage('范围太大，请重新输入区间端点!')elsebeginsushu:=[0..k];for i:=2 to n-1 dofor j:=n to m doif j mod i =0 then sushu:=sushu-[j-n];for i:=n to m div 2 dofor j:= i+1 to m doif j mod i =0 then sushu:=sushu-[j-n];s:='';s0:='';for i:=n to m doif i-n in sushu thenbeginif length(s0+' '+inttostr(i))>60 thenbegins:=s+s0+chr(13);s0:=''end;s0:=s0+' '+inttostr(i);end;s:=s+s0;label1.caption:=s;groupbox1.Top:=(panel1.Top-groupbox1.height) div 2;end;end;procedure TForm1.FormCreate(Sender: TObject);begingroupbox1.Top:=(panel1.Top-groupbox1.height) div 2;end;procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char); var j:set of char;beginj:=['0'..'9',#8];if not(key in j) then key:=#0;end;end.148页12题整除的数implementation{$R *.dfm}function d7(x:integer):boolean;beginif x mod 7=0 then d7:=trueelse d7:=false;end;function d17(x:integer):boolean;beginif x mod 17=0 then d17:=trueelse d17:=false;end;procedure TForm1.FormActivate(Sender: TObject);varn:integer;beginfor n:=1000 to 4000 doif d7(n)and d17(n) then memo1.Lines.Add(inttostr(n)); end;end.148页17题求斐波那契数列问题implementation{$R *.dfm}function fib(n:integer):int64;begincase n of1,2:fib:=1;elsefib:=fib(n-1)+fib(n-2);end;end;procedure TForm1.Button1Click(Sender: TObject);vark:integer;beginmemo1.lines.clear;for k:=1 to strtoint(edit1.text) domemo1.lines.add(format('%2d %3d',[k,fib(k)]));end;end.120页10题，判断是否是闰年procedure TForm1.Button1Click(Sender: TObject);vary,m:integer;beginy:=strtoint(edit1.text);m:=strtoint(edit2.text);label3.Caption:='';if((y mod 4 = 0) and (y mod 100 <> 0)) or (y mod 400=0) then label3.Caption:=edit1.text+'年是闰年,'elselabel3.Caption:=edit1.text+'年不是闰年,';case m of3,4,5:Label3.Caption:=Label3.Caption+edit2.Text+'月份是春天,'; 6,7,8:Label3.Caption:=Label3.Caption+edit2.Text+'月份是夏天,'; 9,10,11:Label3.Caption:=Label3.Caption+edit2.Text+'月份是秋天,'; elseLabel3.Caption:=Label3.Caption+edit2.Text+'月份是冬天,';end;case m of1,3,5,7,8,10,12:Label3.Caption:=Label3.Caption+'共有31天,';4,6,9,11:Label3.Caption:=Label3.Caption+'共有30天,';elseif((y mod 4 = 0) and (y mod 100 <> 0) or (y mod 400=0)) then Label3.Caption:=Label3.Caption+'共有29天,'elseLabel3.Caption:=Label3.Caption+'共有28天,';end;end;end.120页11题求和的procedure TForm1.Button1Click(Sender: TObject);varn,k,j:integer;s:int64;beginn:=strtoint(edit1.text);j:=0;s:=0;for k:=1 to n dobeginj:=j+k;s:=s+j;end;panel2.Caption:=format('s = %d',[s]);edit1.setfocus;end;procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char); var b:boolean;beginb:=(key<>#8)and(key<#48)or(key>#57);if b then key:=#0;end;end.120页12题男人，女人，小孩各有多少人procedure TForm1.Button1Click(Sender: TObject);varx,y,z:integer;p:string;beginmemo1.clear;for x:=0 to 16 dofor y:=0 to 24 dobeginz:=30-x-y;if 3*x+2*y+z/1=50 thenbeginp:=format('%3d %3d %3d',[x,y,z]);memo1.lines.add(p);end;end;end;end.98页2题求长方体的表面积procedure TForm1.Button1Click(Sender: TObject);vars,l,k,h:double;beginl:=strtofloat(edit1.text);k:=strtofloat(edit2.text);h:=strtofloat(edit3.text);s:=2*l*k+2*k*h+2*l*h;label1.Caption:=floattostr(s);end;end.98页5题计算圆的面积和周长procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char); varr:real;b:boolean;beginb:=(key<>#8)and(key<>'.')and(key<>#13)and(key<#48)or(key>#57); if b then key:=#0;if key =#13 thenbeginif edit1.text='' then edit1.text:='0';r:=strtofloat(edit1.text);if radiobutton1.Checked thenlabel1.Caption:=format('圆的面积为：%f',[pi*r*r]);if radiobutton2.Checked thenlabel1.Caption:=format('圆的周长为：%f',[2*pi*r]);if radiobutton3.Checked thenlabel1.Caption:=format('圆的面积为：%f'+chr(13)+ '周长为: %f',[pi*r*r,2*pi*r]); edit1.SelectAll;end;end;procedure TForm1.RadioButton1Click(Sender: TObject);varsender0:tobject;key:char;beginsender0:=edit1;key:=#13;form1.edit1keypress(sender0,key);end;procedure TForm1.RadioButton2Click(Sender: TObject);varsender0:tobject;key:char;beginsender0:=edit1;key:=#13;form1.edit1keypress(sender0,key);end;procedure TForm1.RadioButton3Click(Sender: TObject);varsender0:tobject;key:char;beginsender0:=edit1;key:=#13;form1.edit1keypress(sender0,key);end;end.98页6题统计奇数和偶数的个数procedure TForm1.Button1Click(Sender: TObject);vark,j,n:word;begink:=0;n:=combobox1.items.count;for j:=1to n doif strtoint(combobox1.items[j-1]) mod 2 = 0 thenk:=k+1;label1.caption:=format('共有: '+#13+'%d个偶数，'+#13+'%d个奇数。