字符串轉json

function str2json(str) {
    var arr = str.split('.'), json = {}, _this = json;
    
    if (!json[arr[0]]) json[arr[0]] = {};
    
    for (var i = 0, len = arr.length; i < len; i++) if (_this[arr[i]]) _this = _this[arr[i]]; else _this = _this[arr[i]] = {};
    
    return json;
}

alert(str2json('damai.search.history'));