1. 程式人生 > >Solidity中uint轉string

Solidity中uint轉string

  在《Solidity中uint轉bytes》中,我們知道unit如何轉換成bytes,其實把uint轉換成string,就是在最後加上string(bytes變數)即可,如下所示:

pragma solidity ^0.4.2;

contract Test {

function toBytesNickJohnson(uint256 x) constant returns (bytes b) {
b = new bytes(32);
assembly { mstore(add(b, 32), x) }
}

function getStr(uint playChoice) returns (string s) {
bytes memory c = toBytesNickJohnson(playChoice);
return string(c);
}

function toBytesEth(uint256 x) constant returns (bytes b) {
b = new bytes(32);
for (uint i = 0; i < 32; i++) {
b[i] = byte(uint8(x / (2**(8*(31 - i)))));
}
}

function toBytesNicolasMassart(uint256 x) constant returns (bytes c) {
bytes32 b = bytes32(x);
c = new bytes(32);
for (uint i=0; i < 32; i++) {
c[i] = b[i];
}
}
}

 

  但是呢,我在這裡再附加一種Solidity中uint轉string方法,如下所示:

pragma solidity ^0.4.2;

contract Test {

function uint2str(uint i) public returns (string c) {
if (i == 0) return "0";
uint j = i;
uint length;
while (j != 0){
length++;
j /= 10;
}
bytes memory bstr = new bytes(length);
uint k = length - 1;
while (i != 0){
bstr[k--] = byte(48 + i % 10);
i /= 10;
}
c = string(bstr);
}
}