What is ruling on a woman's getting her haircut by a man?

What is ruling on a woman's getting her haircut by  by men?

It is absolutely not permissible for a woman to get her haircut by a male hairdresser. Because women are required to cover their bodies and their heads in front of a namahram man (a man whom a woman is eligible to marry)

"O Prophet! Tell thy wives and thy daughters and the women of the believers to draw their cloaks close round them (when they go abroad). That will be better, so that they may be recognised and not annoyed. Allah is ever Forgiving, Merciful." (Al-Ahzab, 59)

"And tell the believing women to lower their gaze and be modest, and to display of their adornment only that which is apparent, and to draw their veils over their bosoms, and not to reveal their adornment save to their own husbands or fathers or husbands' fathers, or their sons or their husbands' sons, or their brothers or their brothers' sons or sisters' sons, or their women, or their slaves, or male attendants who lack vigour, or children who know naught of women's nakedness. And let them not stamp their feet so as to reveal what they hide of their adornment. And turn unto Allah together, O believers, in order that ye may succeed. " (Al-Noor, 31)

Awrah (Private Parts) of Women in front of Men according to the four mazhabs

Awrah: Private parts of the body, for both men and women, which must be covered with clothing according to Islam

According to Hanafi Mazhab:

A woman's whole body is awrah except her hands and face.

There is a controversy about feet being awrah. But according to the most authentic opinion, feet are not awrah. And if there is a fear of fitnah (temptation) hands and face should be covered as well.

According to Shafii Mazhab:

Including hands and face, a woman's whole body is awrah in front of non-mahram men.

The hands and the face are not awrah in front of unbeliever women. And the women of low moral standards are assumed as unbeliever about awrah even tough they are Muslims.

According to Maliki Mazhab:

A woman's awrah in front of mahram men is her whole body except her head, neck, hands and feet. Thereby women are not allowed to show their bosom and their legs even to the mahram men.

A woman's awrah in front of a namahram man is her whole body except her hands and face. But what is much better for her is to cover her whole body including her face and hands. (ta'meem)

As for the unbeliever women, a Muslim woman should not show any part of her body including her hands and face.

According to Hanbali Mazhab:

A woman's awrah in front of mahram men is her whole body except her face, neck, head, hands, feet and legs. As for namahram men, her whole body is awrah including her face and hands. (Faruq Bashar)

In conclusion, it is haram for a woman to get a new haircut by a male hairdresser.