如何在C#函数中返回ADO.NET中的计数值？

using System;
using System.Data;
using System.Data.SqlClient;

public class MyClass
{
    public int GetRowCount()
    {
        string connectionString = "连接字符串";
        int count = 0;

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();

            string query = "SELECT COUNT(*) FROM 表名";
            using (SqlCommand command = new SqlCommand(query, connection))
            {
                count = (int)command.ExecuteScalar();
            }

            connection.Close();
        }

        return count;
    }
}