JavaScript: typeOf.js

typeOf.js

function typeOf(obj) {
    var _toString = Object.prototype.toString;
    var _type ={
      "undefined" : "undefined",
      "number" : "number",
        "boolean" : "boolean",
        "string" : "string",
        "[object Function]" : "function",
        "[object RegExp]" : "regexp",
    	"[object Array]" : "array",
    	"[object Date]" : "date",
    	"[object Error]" : "error"
    }

    return _type[typeof obj] || _type[_toString.call(obj)] || (obj ? "object" : "null");
}