Electric cars are basically non gasoline, fuel or diesel powered engine vehicles, they are quiet different from our conventional vehicles. Most electric cars use an electric motor powered by electricity and served through batteries, or a fuel cell. This means that a vast majority of electric cars are either battery or hydrogen powered.
If all stated above is the same understanding you have about electric vehicles, then I definitely think electric vehicles have a future, a future where they will dominate and take over from fuel based vehicles. We've already seen a huge strive taken in other forms of transportation like rail transportation which are mostly powered by electricity or other forms of energy asides fuel. Recently, an electric powered airplane completed flight test to maximum satisfaction. It's only a matter of time before cars follow in these path.
Recently, the world has to come to accept the fact that our planet is heating up and drastic steps need to be taken in order have a conducive and better earth in the future. Am talking about global warming. Though some process involved in industrialization has been partially labeled as part causes of global warming, the key factor which the world has all agreed as major cause of global warming is the continuous burning of fossil fuel and emissions of gases into the earth's atmosphere. This is one major reason why electric cars will be the future.
Countries like France and China which are leading nations in the production of cars have already started to engage in a process which in a few years will see them transition completely from producing fuel based cars to electric powered vehicles. France has said by 2022, almost all fuel cars will no longer be in production thereby leading to electric cars dominating their markets. It's only a matter of time before other countries follow in their steps.
Going back to the question, electric cars as of now are still in the processes of advancing to becoming more reliable. Most of the electric cars available are time based with regards to their generated power. I think best i've seen is an electric car that can last between 60 - 200 miles at most before it requires charging. Hence, i won't say electric cars have evolved to a standard that they can be substituted for fuel based cars for now.