package com.id2ip; import android.app.Activity; import android.os.Bundle; import android.widget.*; import android.view.*; public class id2ip extends Activity {  /** Called when the activity is first created. */  private TextView text;  private Button button;  @Override  public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.main);  //獲得文本框ID  text = (TextView)findViewById(R.id.editText1);  //獲得按鈕ID  button = (Button)findViewById(R.id.button1);  //重載按鍵監聽方法  button.setOnClickListener(new Button.OnClickListener()  {   @Override   public void onClick(View v)   {   //獲得輸入框文本   CharSequence str = text.getText();   do   {    //判斷輸入是否有效    //如果輸入位數不為8位,則無效    if (str.length() != 8)    {    text.setText("輸入位數必須為8位");    break;    }    //輸入的字符不為數字,則無效    int i = 0;    for (i = 0;i < 8;i++)    {    if ((str.charAt(i) < '0') || (str.charAt(i) > '9'))    {     break;    }    }    if (i < 8)    {    text.setText("輸入字符必須為數字");    break;    }    String str_temp = str.toString();    //轉換為數字    long num = Long.parseLong(str_temp);    //ip2id    short slave_num = (short)(num / 1000000);    num = num % 1000000;    short ip1 = (short)(num / 1000);    num = num % 1000;    short ip0 = (short)num;    long num_temp = ip0;    num_temp |= ip1 << 8;    num_temp |= slave_num << 16;    str_temp = Long.toString(num_temp);    str = str_temp;    text.setText(str);   }while (false);   }  });  } }

CharSequence str;String str_temp = str.toString();

str = str_temp;