(转)javascript 如何实现键值对

var variable = 67; 
var map = 
{ 
key 1 : 'string_val', 
key 2 : variable, 
'key 3': function(){alert('blah')}, 
'if the key is not a valid variable name, or is reserved, quote it': true 
}
alert(map.key 1); 
alert(map['key 2']); 
map.key 3(); 
if( map['if the key is not a valid variable name, or is reserved, quote it']) 
alert('OK?');