prefectcalculator.java

java GUI写的一个计算器,功能很全

  char a = s.charAt(i);
  text.setText(text.getText() + a);
  }
  }

  if (temp==ce)
  {
   text.setText("0.");
   clear=true;
   first=1;
  }
  if (temp==c)
  {
   text.setText("0.");   ;
   clear=true;
   first=1;
  }

  if(temp==num0)
   {
    if(clear==false)//判断是否点击了符号位
    text.setText("");
    text.setText(text.getText()+"0");
   }

  if(temp==num1)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"1");
    clear=true;//第二次不在清空（前二句）
   }

  if(temp==num2)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"2");
    clear=true;
   }

  if(temp==num3)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"3");
    clear=true;
   }

  if(temp==num4)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"4");
    clear=true;
   }

  if(temp==num5)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"5");
    clear=true;
   }

  if(temp==num6)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"6");
    clear=true;
   }
  if(temp==num7)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"7");
    clear=true;
   }

  if(temp==num8)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"8");
    clear=true;
   }

  if(temp==num9)
   {
    if(clear==false)
    text.setText("");
    text.setText(text.getText()+"9");
    clear=true;
   }
   if(temp==aa)
   {
    text.setText(text.getText()+"A");
   }
  if(temp==bb)
   {
    text.setText(text.getText()+"B");
   }

  if(temp==cc)
   {
    text.setText(text.getText()+"C");
   }

  if(temp==dd)
   {
    text.setText(text.getText()+"D");
   }

  if(temp==ee)
   {
    text.setText(text.getText()+"E");
   }
  if(temp==ff)
   {
    text.setText(text.getText()+"F");
   }
   if(temp==dian)
   {
    clickable=true;
    for (int i = 0; i < text.getText().length(); i++)
   if ('.' == text.getText().charAt(i))
   {
   clickable=false;
   break;
   } //第一层判断是否里面含有小数点;

    if(clickable==true)//第二坛判断
    text.setText(text.getText()+".");

   }

  try
  {
   if(temp==jia)
   {//加法
    qian=Double.parseDouble(text.getText());
    fuhao="+";
    clear=false;
   }
   if(temp==jian)
   {
    qian=Double.parseDouble(text.getText());
    fuhao="-";
    clear=false;
    ;

   }
   if(temp==cheng)
   {
    qian=Double.parseDouble(text.getText());
    fuhao="*";
    clear=false;

   }
   if(temp==chu)
   {
    qian=Double.parseDouble(text.getText());
    fuhao="/";
    clear=false;

   }
   if(temp==deng)
   {
    double ss=Double.parseDouble(text.getText());
    text.setText("");
    if(fuhao=="+")
    text.setText(qian+ss+"");
    if(fuhao=="-")
    text.setText(qian-ss+"");
    if(fuhao=="*")
    text.setText(qian*ss+"");
    if(fuhao=="/")
    text.setText(qian/ss+"");
    clear=false;//要清空前一次的数据
    ;

   }

   if(temp==kai)
   {
  String s = text.getText();
  if (s.charAt(0) == '-')
  {
   text.setText("负数不能开根号");
  }
  else
  text.setText(Double.toString(java.lang.Math.sqrt(Double.parseDouble(text.getText()))));
  clear=false;
  }

  if(temp==diao)
  {

   if (text.getText().charAt(0) == '0'&&text.getText().length() == 1)
    {
    text.setText("除数不能为零");
    }
  else
  {
  boolean isDec = true;
   int i, j, k;
   String s = Double.toString(1 / Double.parseDouble(text.getText()));
   for (i = 0; i < s.length(); i++)
   if (s.charAt(i) == '.')
   break;
   for (j = i + 1; j < s.length(); j++)
   if (s.charAt(j) != '0')
   {
   isDec = false;
   break;
   }
   if (isDec == true)
   {
   String stemp = "";
   for (k = 0; k < i; k++)
    stemp += s.charAt(k);
    text.setText(stemp);
   }
   else
   text.setText(s);
   }

    clear=false;
  }
  if(temp==qiuyi)
  {
   text.setText("0");
   clear=false;
  }
  if (temp == fu)
  { //导师，此方法参考书中例子
   boolean isNumber = true;
   String s = text.getText();
   for (int i = 0; i < s.length(); i++)
   if (! (s.charAt(i) >= '0' && s.charAt(i) <= '9' || s.charAt(i) == '.' ||
   s.charAt(i) == '-'))
        {
     isNumber = false;
     break;
     }
   if (isNumber == true)
    {
   //如果当前字符串首字母有'-'号,代表现在是个负数,再按下时,则将首符号去掉
     if (s.charAt(0) == '-')
     {
     text.setText("");
     for (int i = 1; i < s.length(); i++)
         {
       char a = s.charAt(i);
       text.setText(text.getText() + a);
           }
     }
      //如果当前字符串第一个字符不是符号，则添加一个符号在首字母处
   else
   text.setText('-' + s);
   }
  }

 }
 catch(Exception eee)
 {
  System.out.println("运算时,首先输入数字或字符");
  text.setText("运算出错");
  clear=false;
 }



 }



 class WindowDestroyer extends WindowAdapter
 {//退出窗口动作
  public void windowClosing(WindowEvent e)
  {
  System.exit(0);
  }
 }

class objConversion
{//导师,本进制类参考了CSMD类转换例子

 public void objConversion ()
 {
 }

 public String decDec (int decNum)
 {//10

  String strDecNum = Integer.toString(decNum);

  for (int i = strDecNum.length(); i < 3; i++)
  {
   strDecNum = "0" + strDecNum;
  }

 // return strDecNum;
  return invert (strDecNum, 5);

 }

 public String decHex (int decNum)
 {//10 to 16

  String strHexNum = "";
  int currentNum = 0;

  while (decNum != 0)
  {

   if (decNum > 15)
   {

    currentNum = decNum % 16;
    decNum /= 16;

   }
   else
   {

    currentNum = decNum;
    decNum = 0;

   }

   switch (currentNum)
   {

    case 15: strHexNum += "F";
       break;
    case 14: strHexNum += "E";
       break;
    case 13: strHexNum += "D";
       break;
    case 12: strHexNum += "C";
       break;
    case 11: strHexNum += "B";
       break;
    case 10: strHexNum += "A";
       break;
    default: strHexNum += Integer.toString(currentNum);
       break;

   }

  }

  return invert (strHexNum, 2);

 }

 public String decOct (int decNum)
 {//10 to 8

  String strOctNum = "";

  while (decNum != 0)
  {

   if (decNum > 7)
   {

    strOctNum += Integer.toString(decNum % 8);
    decNum /= 8;

   }
   else
   {

    strOctNum += Integer.toString(decNum);
    decNum = 0;

   }

  }

  return invert (strOctNum, 3);

 }

 public String decBin (int decNum)
 {//10 to 2

  String strBinNum = "";

  while (decNum != 0)
  {

   if (decNum > 1)
   {

    strBinNum += Integer.toString(decNum % 2);
    decNum /= 2;

   }
   else
   {

    strBinNum += Integer.toString(decNum);
    decNum = 0;

   }

  }

  return invert (strBinNum, 8);

 }

 private String invert (String strNum, int minLength) //转换长度
 {

  String answer = "";
  int length = strNum.length();

  if (length < minLength)
  {

   for (int padding = (minLength - length); padding > 0; padding--)
   {
    answer += "0";
   }

  }

  for (int i = length; i > 0; i--)
  {
   answer += strNum.charAt (i - 1);
  }

  return answer;

 }

}


 public static void main(String arg[])//产生窗口
 {
  PrefectCalculator win = new PrefectCalculator();
  win.setVisible(true);
 }


}