【转载】solidity智能合约[15]-fixtostring


#1

固定字节数组转string

固定字节数组转换为string没有好的办法,必须要首先将固定字节数组转换为动态字节数组,再将动态字节数组转换为string

//bytes2  ->  bytes   ---->string
  function fixtostr(bytes32 _newname) pure public returns(string){


    bytes memory newName = new bytes(_newname.length);

    for(uint i = 0;i<newName.length;i++){
        newName[i] =  _newname[i];
    }

    return string(newName);
}

上面的函数传递0x6a6f的时候,返回的结果为"bytes32 newname": "0x6a6f000000000000000000000000000000000000000000000000000000000000
这显然不是我们想要的。这是由于新建的动态数组的长度为32的原因。下面对其进行改进:

function fixtostr2(bytes32 _newname) pure public returns(string){
  //计数
   uint count = 0 ;

   for(uint i = 0;i<_newname.length;i++){
       bytes1 ch = _newname[i];
       if(ch !=0){
           count++;
       }
   }

   bytes memory name2 = new bytes(count);

   for(uint j = 0;j<name2.length;j++){
       name2[j] = _newname[j];
   }
   return string(name2);
}
  • 本文链接: <https ://dreamerjonson.com/2018/11/19/solidity-15-fixtostring/>