Islamic Dress Code for Men
Question

In the Quran, it has clearly mentioned how women should be dressed in any country or environment whether in an Islamic country or  a non-Islamic country. I want to know, how should men be dressed in any country or environment whether in an Islamic country or in a non-Islamic country?
Praise be to Allah.There follows a summary of the rulings on dress for men. We ask Allah to make it sufficient and beneficial. 

The basic principle concerning everything that is worn is that it is halal and permissible, except for that concerning which there is a text to state that it is haram, such as silk for males. Prophet Muhammad (peace and blessings of Allah be upon him) said: “These two [gold and silk] are forbidden for the males of my ummah and permissible for the females.” (Narrated by Ibn Majah, 3640; classed as sahih by al-Albani in Sahih Ibn Majah)

Similarly it is not permissible to wear the skin of a dead animal (one that has died of natural causes) unless it has been tanned.
With regard to wearing clothes made of wool, goat hair and camel hair, these are pure and permissible. For more information on the use of the skin of dead animals after tanning, please see these answers:  no. 1695  and 9022 .

It is not permissible to wear thin or see-through clothing that does not conceal the ‘awrah.
It is haram to imitate the polytheists and unbelievers in their manner of dress , so it is not permissible to wear clothing that is unique to the unbelievers.

‘Abd-Allah ibn ‘Amr ibn al-‘As said: The Messenger of Allah (peace and blessings of Allah be upon him) saw ‘Ali wearing two garments dyed with safflower and said: “These are garments of the unbelievers; do not wear them.” (Narrated by Muslim, 2077)

It is haram for women to imitate men and men to imitate women in the way they dress. The Prophet (peace and blessings of Allah be upon him) cursed the men who imitate women and the women who imitate men.” (Narrated by al-Bukhari, 5546)
It is Sunnah for a Muslim to start with the right when dressing, and to say, Bismillah (In the name of Allah), and to start with the left when taking clothes off.

Abu Hurayrah said: The Messenger of Allah (peace and blessings of Allah be upon him) said: “When you get dressed and when you do wudu, start on the right.” (Narrated by Abu Dawud, 4141; classed as sahih by al-Albani in Sahih al-Jami’, 787) 

It is Sunnah for the one who is putting on a new garment to thank Allah and make du`a.

Abu Sa’id said: When the Messenger of Allah (peace and blessings of Allah be upon him) put on a new garment, he would call it by its name, whether it was a turban, a shirt or a cloak, then he would say: “Allahumma laka al-hamd anta kasawtanihi asaluka khayrahu wa khayra ma suni’a lah wa a’udhu bika min sharrihi wa sharri ma suni’a lah (O Allah, to You be all praise. You have clothed me with it. I ask You for the good of it and the good for which it was made, and I seek refuge with You from the evil of it and the evil for which it was made).” (Narrated by al-Tirmidhi, 1767; Abu Dawud, 4020; classed as sahih by al-Albani in Sahih al-Jami’, 4664)

It is Sunnah to pay attention to keeping one's clothes clean, without feeling arrogant or exaggerating about that.

‘Abd-Allah ibn Mas’ud narrated that the Prophet (peace and blessings of Allah be upon him) said: “No one will enter Paradise in whose heart is a mustard-seed of arrogance.” A man said: “What if a man likes his clothes to look nice and his shoes to look nice?” He said: “Allah is Beautiful and loves beauty; arrogance means rejecting the truth and looking down on people.” (Narrated by Muslim, 91)

It is mustahabb to wear white clothes

Ibn 'Abbas said: The Messenger of Allah (peace and blessings of Allah be upon him) said: “Wear white clothes, for they are the best of your clothes, and shroud your dead in them.” (Narrated by al-Tirmidhi, 994, hasan sahih. This is what the scholars regarded as mustahabb. Also narrated by Abu Dawud, 4061; Ibn Majah, 1472. )

It is haram for the Muslim man to let any garment he wears hang down beneath his ankles (an action known as isbal ); the limit for any garment is the ankles.

Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) said; “Whatever of the lower garment is beneath the ankles is in the Fire.” (Narrated by al-Bukhari, 5450) 
Abu Dharr narrated that the Prophet (peace and blessings of Allah be upon him) said: “There are three to whom Allah will not speak on the Day of Resurrection and will not look at them or praise them, and theirs will be a painful torment.” The Messenger of Allah (peace and blessings of Allah be upon him) repeated it three times. Abu Dharr said: “May they be doomed and lost; who are they, O Messenger of Allah?” He said: “The one who lets his garment hang beneath his ankles, the one who reminds others of favours he has done, and the one who sells his product by means of false oaths.” (Narrated by Muslim, 106)

It is haram to wear garments of fame and vanity, which means a garment that stands out from others so that people will look at the wearer and he will become known for it.

Ibn ‘Umar said: The Prophet (peace and blessings of Allah be upon him) said: “Whoever wears a garment of fame and vanity, Allah will dress him in a garment like it on the Day of Resurrection.” 
According to another version, “…then set it ablaze.” And according to a third version, “will dress him in a garment of humiliation.” (Narrated by Abu Dawud, 4029; Ibn Majah, 3606 and 3607; classed as hasan by Shaykh al-Albani in Sahih al-Targhib, 2089) 
The brother may also refer to the section on Dress in this website, where there is more information. 
And Allah knows best.