c#中如何去除最后一个符号。

class Program
{
static void Main(string[] args)
{
string aaa = "aa;bb;cc;dd";
string bbb = aaa.Replace(';',',');
string[] ccc = bbb.Split(',');
//System.Console.WriteLine(aaa);
//System.Console.WriteLine(bbb);
StringBuilder sb = new StringBuilder("(");
foreach (string c in ccc)
{
sb.Append(c);
sb.Append(",");
}

sb.Remove((sb.Length - 1),1);
sb.Append(")");
System.Console.WriteLine(sb);
}
}