用java编写一个简易的计算器代码

1、导入Java.awt.borderlayout；导入Java.awt.color；导入Java.awt.gridlayout；导入Java.awt.event.actionevent；导入Java.awt.event.action监听器；导入Java.awt.event.keyevent；导入Java.awt.event.key监听器；导入javax.swing.jbutton；导入javax.swing.jframe；导入javax.swing.jpanel；导入javax.swing.jtextfield；使用java语言开发简单的计算机*/publicclasstestjsqtexten

2、sjframeimplementsactionlistener，KeyListener 。私有jtextfield jtf；私有jbutton JB _ bk、jb_ce、jb_c；私有字符串xs=；私有双求和=0；私有int FH；publicstaticvoidmain (string args ) new TestJsq().creatCUI ()；以下publicvoidacreatcui ()； 请参见。JFrame jf=new JFrame ()；jf.setTitle (计算机 )；jtf=new JTextField(0. )；jtf.setrhorizntalaligenv

3、ironmentt (jtextfield.right )jf.add(jtf，BorderLayout.NORTH )jpanel jp _ main=new jpanel (newborderayout ()；PS.PSjpanel jp1=new jpanel (new gridlayout (1，3，1，1 ) )；jb_bk=new JButton(Backspace )JB _ bk.set foreground (颜色. red )jb_bk.addActionListener(this )JB_ce=newjbutton(ce )；jb_ce.setForeground(Col

4、or.RED )jb_ce.addActionListener(this )JB _ c=新jbutton ( c )；JB _ c.set foreground (颜色. red )jb_c.addActionListener(this )PS1. PS (PS _ S )jp1.添加(JB _ ce )jp1.添加(JB _ c )jp_main.add(jp1，BorderLayout.NORTH )jpanel jp2=new jpanel (newgridyout (4，5，1，1 ) )；字符串str = 7，8，9，/， sqrt ，4，5，6， * ， % ，“1”、“2”、“

5、3”、“-”、“1/x”、“0”、“/-”、“=“；for (int i=0； i 20； 表示I )JButton jb=new JButton(stri )；jb.addActionListener(this )jb.setForeground(Color.blue )假设if (I=3|I=8|I=13| I=18| I=19 ) )jb.setForeground(Color.RED )以下jp2 .添加(JB )以下jp_main.add(jp2，BorderLayout.CENTER )jf.setResizable(false )JF.set bounds (50，50，350，

6、350 )jf.setVisible(true )以下Overridepublicvoidactionperformed (actionevent e ) String s=e.getActionCommand ()；接着if (s.equals ( ce )| s.equals ( c ) *。xs=；jtf.setText(0. )；输入elseif(s.equals(backspace)String str=xs.substring(0，xs.length() - 1 )xs=str；jtf.setText(xs )else if (s.equals (7 )| s.equals (8

7、)| s.equals (9 )|s.quals (4 )| s.equals (5 )| s.equals (6 )|s.equals (1 )| s.equals (2 )| s.equals (3 )| s.equals (0 )| s.equals (. )xs=xs s；jtf.setText(xs )输入 else if (s.equals (/- ) double x=Double.parseDouble(xs )xs= (-x )jtf.setText(xs )请输入elseif(s.equals(/ ) )fh=4；int point=xs.indexOf ( )；PS (点

8、)！=-1 )String strt=xs.substring(0，point )string z=xs.substring (点1，xs.length ()；int z_num=z.length ()；sum=integer.decode (strt ) (双倍) (integer.decode (z ) )/(10 * z_num ) else sum=Integer.decode(xs )以下xs=；jtf.settext (空)请输入elseif(s.equals(* )fh=3；int point=xs.indexOf ( )；PS (点)！=-1 )String strt=xs.s

9、ubstring(0，point )string z=xs.substring (点1，xs.length ()；int z_num=z.length ()；sum=integer.decode (strt ) (双倍) (integer.decode (z ) )/(10 * z_num ) else sum=Integer.decode(xs )以下xs=；jtf.settext (空)请输入elseif(s.equals(- )fh=2；int point=xs.indexOf ( )；PS (点)！=-1 )String strt=xs.substring(0，point )strin

10、g z=xs.substring (点1，xs.length ()；int z_num=z.length ()；sum=integer.decode (strt ) (双倍) (integer.decode (z ) )/(10 * z_num ) else sum=Integer.decode(xs )以下xs=；jtf.settext (空)请输入elseif(s.equals ( ) )fh=1；int point=xs.indexOf ( )；PS (点)！=-1 )String strt=xs.substring(0，point )string z=xs.substring (点1，

11、xs.length () )；int z_num=z.length ()；sum=integer.decode (strt ) (双倍) (integer.decode (z ) )/(10 * z_num ) else sum=Integer.decode(xs )以下xs=；jtf.settext (空)把elseif(s.equals(sqrt)double x=Double.parseDouble(xs )double x1=Math.sqrt(x )xs=x1 ；jtf.setText(xs )请输入elseif(s.equals(% )double x=Double.parseDo

12、uble(xs )x=0.01 * x*x；xs=x ；jtf.setText(xs )输入elseif(s.equals(1/x)输入if(xs=0 )，输入jtf.setText (除数为0 )； else double x=Double.parseDouble(xs )双精度x1=1/x；xs=x1 ；jtf.setText(String.valueOf(xs ) )；以下请输入elseif(s.equals(= )PS (PS！=0)打开交换机(FH ) 0case 1:int point1=xs.indexOf ( )；PS (点1！=-1 )String s1=xs.substri

13、ng(0，point1)string Z1=xs.substring (点1，xs.length () )；int z1_num=z1.length ()；xs=；double ss1=Integer.decode(s1 )。(双倍)整数解码(z1)/(10 * z1_ num )sum=sum ss1； else sum=sum Integer.decode(xs )xs=；以下fh=0；break；case 2:int point2=xs.indexOf ( )；PS (点2！=-1 )String s2=xs.substring(0，point2)string z2=xs.substring (点2，xs.length () )；int z2_num=z2.length ()；xs=；double ss2=Integer.decode(s2 )。(双倍)整数解码(z2)/(10 * z2_ num )sum=sum - ss2； else sum=su