如何在单个参数的where子句中传递多个值

I have faced this situation first time. Here I have to pass multiple values for a single argument and also it is not necessary that the argument will always have multiple values. Sometimes 1 sometimes it will be 2 or also 3. So how do I write it in where clause I am confused in that. I have looked for the various source but I am not geting how to I do exactly this thing. Someone suggests to use dynamic query but is there any easy way to do it. I will post a pseudo code please suggests me how should do it or what the best way to this. I have faced this situation first time. Here I