Solidity中固定大小字节数组转string

string本身是一个特殊的动态字节数组，所以它只能和bytes之间进行转换，不能和固定大小字节数组进行直接转换，如果是固定字节大小数组，需要将其转换为动态字节大小数组才能进行转换。

``
pragma solidity ^0.4.4;

contract C {

function bytes32ToString(bytes32 x) constant returns (string) {
    bytes memory bytesString = new bytes(32);
    uint charCount = 0;
    for (uint j = 0; j < 32; j++) {
        byte char = byte(bytes32(uint(x) * 2 ** (8 * j)));
        if (char != 0) {
            bytesString[charCount] = char;
            charCount++;
        }
    }
    bytes memory bytesStringTrimmed = new bytes(charCount);
    for (j = 0; j < charCount; j++) {
        bytesStringTrimmed[j] = bytesString[j];
    }
    return string(bytesStringTrimmed);
}

function bytes32ArrayToString(bytes32[] data) constant returns (string) {
    bytes memory bytesString = new bytes(data.length * 32);
    uint urlLength;
    for (uint i = 0; i< data.length; i++) {
        for (uint j = 0; j < 32; j++) {
            byte char = byte(bytes32(uint(data[i]) * 2 ** (8 * j)));
            if (char != 0) {
                bytesString[urlLength] = char;
                urlLength += 1;
            }
        }
    }
    bytes memory bytesStringTrimmed = new bytes(urlLength);
    for (i = 0; i < urlLength; i++) {
        bytesStringTrimmed[i] = bytesString[i];
    }
    return string(bytesStringTrimmed);
}    

}
``