Parameterized Queries with LIKE and IN conditions

Parameterized Queries in .Net always look like this in the examples:

SqlCommand comm = new SqlCommand(@"
   SELECT * 
   FROM   Products 
   WHERE  Category_ID = @categoryid
", 
   conn);
comm.Parameters.Add("@categoryid", SqlDbType.Int);
comm.Parameters["@categoryid"].Value = CategoryID;

But I'm running into a brick wall trying to do the following:

SqlCommand comm = new SqlCommand(@"
   SELECT * 
   FROM   Products 
   WHERE  Category_ID IN (@categoryids) 
      OR  name LIKE '%@name%'
", 
   conn);
comm.Parameters.Add("@categoryids", SqlDbType.Int);
comm.Parameters["@categoryids"].Value = CategoryIDs;
comm.Parameters.Add("@name", SqlDbType.Int);
comm.Parameters["@name"].Value = Name;

Where

• CategoryIDs is a comma separated list of numbers "123,456,789" (without quotes)
• Name is a string, possibly with single quotes and other bad characters

What's the right syntax for this?