无法访问静态上下文中的非静态字段 [字段名称]

基类：

public class DatabaseBase
{
  private readonly string connectionString;
  private bool useCounters;

  public DatabaseBase(string connectionString)
  {
   this.connectionString = connectionString;
  }

  public DatabaseBase(...)
  {
   connectionString = ...;   
  }

  public DatabaseBase(..)
  {
   connectionString = string.Format(...);
  }

  public string ConnectionString
  {
   get { return this.connectionString; }
  }

...

派生类：

public class ProjectDB : DatabaseBase
{
private bool useServiceConnection;

 private static string ConnectionString
 {
     get
     {
        string connectionString = useServiceConnection == true ? ConfigurationManager.AppSettings["SomeConnection1"] : ConfigurationManager.AppSettings["SomeConnection2"];
         return connectionString;
     }
 }


public ProjectDB() : this(false)
{
}

 private bool isServiceCall;

public ProjectDB(bool useServiceConnection)
    : base(ConnectionString)
{
    this.useServiceConnection = useServiceConnection;
}

private SqlConnection CreateConnection()
{
    return new SqlConnection(ConnectionString);
}

我收到此行的错误“无法在静态上下文中访问非静态字段 useServiceConnection”：

string connectionString = useServiceConnection == true ? ConfigurationManager.AppSettings["SomeConnection1"] : ConfigurationManager.AppSettings["SomeConnection2"];

但是，如果我将 useServiceConnection 设为静态变量来满足要求，那么我会在构造函数中遇到相同的错误：

public ProjectDB(bool useServiceConnection)
    : base(ConnectionString)
{
    this.useServiceConnection = useServiceConnection;
}

现在，如果我将 useServiceConnection 和 ConnectionSting 属性设置为非静态，那么我会在此处收到构造函数的错误：

public LitleDB(bool useWebServiceConnection)
    : base(ConnectionString)
{
    this.useWebServiceConnection = useWebServiceConnection;
}

我想前两个我理解。

但现在更新了下面的示例，为什么这种情况下的构造函数仍然会给我一个错误？这些不再是静态的，那么静态上下文从哪里来呢？这就是我现在所拥有的：

public class ProjectDB : DatabaseBase
 {
    private bool useServiceConnection; <-- NO LONGER STATIC

     private new string ConnectionString <-- NO LONGER STATIC
     {
         get
         {
            string connectionString = useServiceConnection == true ? ConfigurationManager.AppSettings["SomeConnection1"] : ConfigurationManager.AppSettings["SomeConnection2"];
             return connectionString;
         }
     }

    public ProjectDB() : this(false)
    {
    }

     private bool isServiceCall;

    public ProjectDB(bool useServiceConnection)
        : base(ConnectionString)  <--- IT'S COMPLAINING HERE NOW, SO WHERE IS IT TRYING TO ACCESS STATICALLY?  I DON'T GET WHY
    {
        this.useServiceConnection = useServiceConnection;
    }

我在这个类中有其他静态属性，这有什么关系吗？不过我没有使用它们。

变量useServiceConnection is not static所以它只存在于类实例的上下文中。自该物业ConnectionString是静态的，它不存在于实例的上下文中，因此它无法“查看”实例成员。你需要做ConnectionString不是静态的，或者使useServiceConnection static.