is-address/index.js

以太坊web3.js中的isAddress

const Hex = require('crypto-js/enc-hex'),
    Sha3 = require('crypto-js/sha3');

const sha3 = (value, options) =>{
    if (options && options.encoding === 'hex') {
        if (value.length > 2 && value.substr(0, 2) === '0x') {
            value = value.substr(2);
        }
        value = Hex.parse(value);
    }

    return Sha3(value, {
        outputLength: 256
    }).toString();
},
    isChecksumAddress = (address)=> {
        address = address.replace('0x','');
        var addressHash = sha3(address.toLowerCase());

        for (var i = 0; i < 40; i++ ) {
            if ((parseInt(addressHash[i], 16) > 7 && address[i].toUpperCase() !== address[i]) || (parseInt(addressHash[i], 16) <= 7 && address[i].toLowerCase() !== address[i])) {
                return false;
            }
        }
        return true;
    };

const isAddress = function (address) {
    if (!/^(0x)?[0-9a-f]{40}$/i.test(address)) {
        return false;
    } else if (/^(0x)?[0-9a-f]{40}$/.test(address) || /^(0x)?[0-9A-F]{40}$/.test(address)) {
        return true;
    } else {
        return isChecksumAddress(address);
    }
};

module.exports=isAddress