// Empty hash table
var hashObject = {};
// Hash table with two key:value pairs:
var hashObject = {"key1":"value1","key2":"value2"};

จะเขียน key แบบไม่มี quote ก็ได้ แต่ต้องไม่ตรงกับคำสงวน

var hashObject = {key : "value"}; // create

hashObject["key"] = "new value"; // add/replace

delete(hashObject["key"]); // delete

for (var i in object) // is equivalent to foreach

Check for a presence of a particular key:
if ("key" in hashObject) // returns true or false