#define NSLocalizedString(key, comment) \
[[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:nil]
#define NSLocalizedStringFromTable(key, tbl, comment) \
[[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:(tbl)]
#define NSLocalizedStringFromTableInBundle(key, tbl, bundle, comment) \
[bundle localizedStringForKey:(key) value:@"" table:(tbl)]
#define NSLocalizedStringWithDefaultValue(key, tbl, bundle, val, comment) \
[bundle localizedStringForKey:(key) value:(val) table:(tbl)]
测试：
注意，下面的request应为NSMutableURLRequest，即可变类型
