Holy matrimony as we all know is a sacrament. According to Canon 843.1, it states clearly that Catholics cannot be denied any sacraments if they opportunely ask for them, if they are properly disposed, and are not prohibited by law from receiving them.
Also, in the recent (1983) Code of Canon Law, there is definitely nothing to indicate that any particular days of the year are definitively off-limits for the celebration of weddings.
Then in 1988, the Congregation for Divine Worship published a document about the Preparation and Celebration of the Easter Feasts which described authoritatively that there are two days when marriages cannot be celebrated.
The first day is On Good Friday. On this day, all celebration of the sacraments is strictly prohibited, except for the Sacraments of Penance and Anointing of the Sick.
The second day is the Holy Saturday, On this day also, the celebration of marriages is forbidden.
However, if any Catholic ever asks his priest to schedule a wedding on Good Friday or Holy Saturday, the answer must be abruptly no. And refusal would thus be fully in accord with canon 843.1.
Though, in case of imminent danger of death, these restrictions on the celebration of matrimony could be lifted.
Note that as canon law does permit a wedding during Lent (except for the two days just discussed above), so the faithful are required to tone down the celebration, so as to keep with these more somber periods of the liturgical year.
For weddings during Lent, the liturgical books of the Church indicate that external signs such as music and flowers are to be less lavish.
Also Note that in the process of making this admonition, the liturgical books hence acknowledge that weddings celebrated during these times cannot just be celebrated with the same exuberance and festivity like weddings held at other times of the year.
Even Funerals are to be celebrated without singing, music, or the tolling of bells.
Enforcing it in law that Catholics can’t get married for the entire calendar period between Ash Wednesday and Easter, in an obvious way constitutes a very loose interpretation of the restrictions contained in canon 843.1, and so, it’s a policy unsupported by the canon law.
So you know that Lent may not be the best time of the year to schedule a happy event like a wedding, but sometimes this is the best (or only!) option for the spouses, and the Church indeed permits the sacramental celebration to take place.