无法在FFMPEG中为C＃.net找到合适的'&&'输出格式

I am trying to convert and delete the source file using FFMPEG, what i want is to convert video file from one format to other, and delete the first one which is uploaded means source file, the command works fine if we use && operator after conversion syntax and write del command, it works well on command line but when we try using c#, it gives the error Unable to find a suitable output format for '&&' I have checked with debugger, and its the same line which we are writing on command line, command line does not have any problem. What's the issue with c#?I am trying to convert and delete the source fi