接着上一个程序

     //进行系列运算
     public void deltwith(char c){
      double currentnumber = Double.valueOf(result.getText()).doubleValue();          
      if(lastchar=='E')        
      numbers=currentnumber;
      else if(lastchar=='+')
      numbers+=currentnumber;
      else if(lastchar=='-')
      numbers-=currentnumber;
      else if(lastchar=='*')
      numbers*=currentnumber;
      else if(lastchar=='÷'){
      try{
      numbers /=currentnumber;     
      }catch(ArithmeticException e){
      result.setText("0.00");
      }
      }
      else if(lastchar=='='&&equaledoperation)
      numbers=currentnumber;
      else if(lastchar=='p')
      numbers=currentnumber*(-1);
      else if(lastchar=='s')
      try{
      numbers=Math.sqrt(currentnumber);
      }catch(Exception e){
      result.setText("0.00");
      }
      lastchar=c;
      if(lastchar=='t')
      numbers=currentnumber*currentnumber;
      else if(lastchar=='r')
      numbers=currentnumber*currentnumber*currentnumber;
      else if(lastchar=='S')
      numbers=Math.sin(currentnumber);
      else if(lastchar=='c')
      numbers=Math.cos(currentnumber);
      else if(lastchar=='a')
      numbers=Math.tan(currentnumber);
      else if(lastchar=='o')
      numbers=1/Math.tan(currentnumber);
      else if(lastchar=='d')
      numbers=1/currentnumber;
      else if(lastchar=='l')                 
      numbers=Math.log10(currentnumber);
      else if(lastchar=='e')
      numbers=1/Math.cos(currentnumber);
      else if(lastchar=='h')
      numbers=1/Math.sin(currentnumber);
       if(lastchar=='D')
      numbers=Double.parseDouble(deletenumber());
       
      result.setText(""+numbers);  
     }
     //删除操作
     public String  deletenumber(){
      string2="";
      double currentnumber = Double.valueOf(result.getText()).doubleValue(); 
  if(currentnumber>=10e13)
  j=14;
  else if(10e13>currentnumber&&currentnumber>=10e12)
      j=13;
      else if(currentnumber>=10e11&&currentnumber<10e12)
  j=12;
  else if(currentnumber>=10e10&&currentnumber<10e11)
  j=11;
  else if(currentnumber>=10e9&&currentnumber<10e10)
  j=10;
  else if(currentnumber>=100000000&&currentnumber<1000000000)
  j=9;
  else if(currentnumber>=10000000&&currentnumber<100000000)
  j=8;
  else if(currentnumber>=1000000&&currentnumber<10000000)
  j=7;
  else if(currentnumber>=100000&&currentnumber<1000000)
  j=6;
  else if(currentnumber>=10000&&currentnumber<100000)
  j=5;
  else if(currentnumber>=1000&&currentnumber<10000)
  j=4;
  else if(currentnumber>=100&&currentnumber<1000)
  j=3;
  else if(currentnumber>=10&&currentnumber<100)
  j=2;
  else if(currentnumber>=1&&currentnumber<10)
  j=1;
     int number[]=new int[j];
  for(int i=0;i<j;++i){
  number[i]=(int)currentnumber%10;
  currentnumber=currentnumber/10;
  }
  for(int i=j-1;i>0;--i)
  string2+=number[i];   
  return string2;
     }
     public static void main(String args[]){
      Calculator calculator=new Calculator();
   }
}