I am currently working as Automation tester in C# selenium is it good to Switch to C development

As far as career progression is concerned the chances are pretty good for both testing as well as development. My elder son is working in Infosys in the testing area only. He got good jumps and promotions in the same company in that same area only. He received appreciation awards and cash rewards also.

So all depends on how best you perform in the area of your work. You should focus on your work and concentrate on developing your skills. Then you will have fast growth. When a product is developed, it is to be tested and proved. During the development also at every stage, the nod of testing people is required to go ahead. That way testing is also a part of development and scope is good.

Already you put up experience in the testing area. So I feel you should continue in the same line so that your experience will be useful and you will have better chances of getting a new post in a good company or promotion in the present company. If you switch over to product development, you may have to prove again in that area also. Use some spare time in improving your present skills and acquiring new skills which will be helpful to you in having a better career.

Both the testing line and the developer have the scopes for the better promotion provided you show excellent performance in your line.
In the area of testing, you have to test the product in different angles and finally the same has to be approved by the tester. Hence a tester will have the knowledge of entire working function of the operating module. A tester having wide experience in the area of own would be entitled to promotion in the quickest span if he is fully aware of the complexities of the testing procedures. He may get appreciation for his commendable performance in the similar line.
By changing your line say in the line of developer, you have to struggle a lot in the initial phase so as to be acquainted with the different aspects of your project. In the wake of intense competition and shortage of staffs, you may not derive benefit of support from any experience hands. This may sometimes cause frustration time to time but you may overcome this situation with your renewed interest in the area of developer.
The best recourse of action would be to take of the job of developer in your leisure time and learn sincerely the different functions in this line and in case of confusion, take the help of colleagues engaged in this line so as to wipe out confusion with which you are coming across. Your consistent approach and the guidance of your colleagues would lead to success in the assignment of developing area.
Enrichment of job in other area apart from the present one would prove to be a plus point in your case and in due course, you would enjoy promotion for your efficiency.

You have to see your interest versus capabilities before switching from one to another. You might be aware that in automatic testing much knowledge of coding is not required but in manual testing it is a must skill. So, there are many combinations in which a job is to be performed in testing. Anyway, the salaries of software tester and software developer are comparable though in many cases the developers are paid slightly on the higher side. If you have good interest in coding and software development areas then you can think of switching from testing to developing.

Moreover a tester has to be versatile in the whole gamut of software techniques while a developer may be working in limited modules only bothering for software development. At the same time the availability of testing automation tools like IBM Rational Functional Tester and Pytest make the life of a tester comfortable. Though tester and developer both are important for the organisations but developer generally have an edge over the testers.

I think you can consider the pros and cons of these two engagements and accordingly take a conscious decision as what to hold and what not to hold.

As you already are working as Automation tester and you want to switch and become a developer. I think it is not a bad idea. Infact with tester experience you will become a good developer. Because you already have a good knowledge, aware about more scenarios of designing software. You will be able to find out bugs or errors in your codes. So overall, you will be more disciplined when it comes to testing and you will be proved as a better software developer.
But for this you have to focus on following aspects:
1. Choose your are of interest.
2. Select technology, with which you can work.
3. After selecting technology you will have to get yourself certified in it.
4. Gain some experiences in the related projects. You can take help of your seniors.
5. After sufficient experience you will be able to work as a software developer.
However, both tester and developer have good career perspectives. But in terms of salaries developers are getting advantage. So if you switch from tester to developer, you will be a developer with good testing knowledge it will be more beneficial for you.
In my opinion, it is good if you ate planning to switch. Switch but with good preparation. You will definitely become a good software developer.

Thanks all for your valuable words!!