this.balance返回该合约地址里的以太坊余额

注意

balance=this.balance//balance需要constant修饰符

pragma solidity ^0.4.22;
/*
+------------------------------------------------------------------------------+
|                                                                              |
|      XX               XXXXX XXXXXX          XXXXXXXXXXX        XXXXXXXXXX    |
|     XX XX           XXX   XXX   XXX         X         X        X        X    |
|    XX   XX          X      X      X         XXXXXXXXXXX        X        X    |
|   XXXXXXXXX         X             X         X                  X        X    |
|  XX       XX        X             X         X                  X        X    |
| XX          X       X             X         XXXXXXXXXXX        X        X    |
|                                                                              |
|                                                                              |
+------------------------------------------------------------------------------+
*/
contract  Balance{
   //存入一些ether用于后面的测试
  function deposit() payable{
  }

  //查询当前的余额
  function getBalance() constant returns(uint){
      return this.balance;
  }
}