啟動sql依賴項時對象名稱無效

Question

這是我的代碼

SqlDependency.Start(GetConnectionString(), getQuery());

其中getQuery()是：

private string getQuery() {
            return "SELECT firstName, lastName FROM dbo.Customer";
        }

我有這個例外：

Invalid object name 'SELECT firstName, lastName FROM dbo.Customer'.

更新資料

    private string getQuery() {
        return "SELECT firstName, lastName FROM dbo.Customer";
    }

    public void Initialization()
    {
        // Create a dependency connection.
        SqlDependency.Start(GetConnectionString(), getQuery());
    }


    public void SomeMethod()
    {
        // Assume connection is an open SqlConnection.

        // Create a new SqlCommand object.
        using (SqlCommand command = new SqlCommand(
            getQuery(),
            new SqlConnection(GetConnectionString())))
        {
            // Create a dependency and associate it with the SqlCommand.
            SqlDependency dependency = new SqlDependency(command);
            // Maintain the refence in a class member.
            // Subscribe to the SqlDependency event.
            dependency.OnChange += new
               OnChangeEventHandler(OnDependencyChange);
            // Execute the command.
            using (SqlDataReader reader = command.ExecuteReader())
            {
                // Process the DataReader.
            }
        }
    }

然后從外面，我這樣做：

printing p = new printing();
            p.Initialization();
            p.SomeMethod();

Answer 1

您正在使用SqlDependency.Start(string, string)重載，其中第二個字符串表示隊列名稱。 'SELECT firstName, lastName FROM dbo.Customer'不是有效的隊列名稱。

您需要為查詢創建一個SqlCommand並將其注入到構造函數中 ：

var dependencyCommand = new SqlCommand();
dependencyCommand.CommandText = getQuery();

sqlDependency = new SqlDependency(dependencyCommand);
sqlDependency.Start(GetConnectionString());

---

至於編輯，您已經完成了。 只需刪除SqlDependency.Start()的第二個參數即可。