将参数中的变量插入到Sql Command查询中

Question

这是我在类文件中的代码：

public class terminarzLiga
{
    public static List<terminarz> wyswietlTerminarz(string liga)
    {
        List<terminarz> wyswietlTerminarz = new List<terminarz>();
        string CS = ConfigurationManager.ConnectionStrings["ligiConnection"].ConnectionString;
        using (SqlConnection con = new SqlConnection(CS))
        {
            SqlCommand com = new SqlCommand("Select * from TerminarzLaLiga", con);
            con.Open();
            SqlDataReader rdr = com.ExecuteReader();
            while (rdr.Read())
             [.... rest of code .....]

我的意图是在Sql Command查询中使用变量，如下所示： 代码背后：

private void ZaladujGridView()
{
    GridView2.DataSource = EuroPilka.terminarzLiga.wyswietlTerminarz("TerminarzLaLiga");
    GridView2.DataBind();
}

班级文件代码：

public class terminarzLiga
{
    public static List<terminarz> wyswietlTerminarz(string liga)
    {
        List<terminarz> wyswietlTerminarz = new List<terminarz>();
        string CS = ConfigurationManager.ConnectionStrings["ligiConnection"].ConnectionString;
        using (SqlConnection con = new SqlConnection(CS))
        {
            SqlCommand com = new SqlCommand("Select * from '" + liga +"'", con);
            con.Open();
            SqlDataReader rdr = com.ExecuteReader();
            while (rdr.Read())
             [.... rest of code .....]

但我在阅读器执行时收到错误

SqlDataReader rdr = com.ExecuteReader();

非常感谢任何建议！