Values maps a string key to a list of values. It is typically used for query parameters and form values. Unlike in the http.Header map, the keys in a Values map are case-sensitive.
Add adds the value to key. It appends to any existing values associated with key.
Delete deletes the values associated with key.
Get gets the first value associated with the given key. If there are no values associated with the key, Get returns the empty string. To access multiple values, use the map directly.
Has check the key exists or not.
IsEmpty check the key is empty or not.