js实现数组转换成json

function arrayToJson(o) {
    var r = [];
    if (typeof o == "string") return """ + o.replace(/(['"\])/g, "\$1").replace(/(n)/g, "\n").replace(/(r)/g, "\r").replace(/(t)/g, "\t") + """;
    if (typeof o == "object") {
      if (!o.sort) {
        for (var i in o)
          r.push(i + ":" + arrayToJson(o[i]));
        if (!!document.all && !/^n?functions*toString()s*{n?s*[native code]n?s*}n?s*$/.test(o.toString)) {
          r.push("toString:" + o.toString.toString());
        }
        r = "{" + r.join() + "}";
      } else {
        for (var i = 0; i < o.length; i++) {
          r.push(arrayToJson(o[i]));
        }
        r = "[" + r.join() + "]";
      }
      return r;
    }
    return o.toString();
  }