Can a landlord evict a commercial tenant by changing the locks and locking the tenanat out prior to a court eviction process If not then what would be the tenants remedie once formal eviction begin?

Someone else's answer, which is WRONG:
A landlord can not lock out a tenant...ever. The only person that can would be the sheriff. You will be notified by way of a notice posted on your door from the sheriff's department notifying you of the exact date and time your locks will be changed. The sheriff will most likely be escorted by the manager or a maintenance member. Once the eviction process begins, your best bet is to return possession of the apartment as soon as possible. The longer you stay, the more you will owe in rent, legal fees etc. In addition, if you intend to ride out the entire eviction, it is guaranteed to be on your credit for 7 years, and it will be extremely difficult to rent anywhere (or purchase a house) until it has been removed.
Actually on a commercial lease a landlord has the right to lock you if this is stipulated in the lease. Best to read your lease on consult a lawyer before taking this action with a Commercial lease.

My answer:
According to Chapter 93, Section 2 of the Texas Property Code, a landlord CAN lock out (change the door locks) of a COMMERCIAL tenant who is delinquent in paying at least part of the rent, and without any judicial process. The landlord or agent must place a written notice on the tenant's front door stating the name and the address or telephone number of the individual or company from which the new key may be obtained. The new key is required to be provided only during the tenant's regular business hours and *only* if the tenant pays the delinquent rent.

I suspect other states have similar laws for COMMERCIAL properties. It might be worth checking out your state's property code for COMMERCIAL property (very different from residential). FYI, Article 2A of the UCC (Uniform Commercial Code) that applies in all 50 states applies to the lease of goods, not real estate.