ServiceEventSource和Service Fabric

Question

使用非常简单的代码来处理异常处理和登录Service Fabric：

public async Task<IActionResult> Get()
{
    ServiceEventSource.Current.ServiceMessage(serviceContext, $"Entered 'GetAll' method");

    IActionResult result = null;
    List<Customer> list = new List<Customer>();

    try
    {
        using (CustomersContext context = new CustomersContext(connectionString))
        {
            list = context.Customers.Where(a => a.IsDeleted == false).ToList<Customer>();
        }
        result = Json(list);

        throw new ArgumentException("Argument exception", new NullReferenceException("Null reference exception"));
    }
    catch (Exception ex)
    {
        result = StatusCode(StatusCodes.Status500InternalServerError);
        ServiceEventSource.Current.ServiceMessage(serviceContext, $"Exception: " + JsonConvert.SerializeObject(ex));
    }
    finally
    {
        ServiceEventSource.Current.ServiceMessage(serviceContext, $"Exiting 'GetAll' method");
    }
    return result;
}

我的问题是：为什么这行代码在开头

ServiceEventSource.Current.ServiceMessage(serviceContext, $"Entered 'GetAll' method");

和finally块中的这行代码

ServiceEventSource.Current.ServiceMessage(serviceContext, $"Exiting 'GetAll' method");

在诊断事件中正常工作并记录条目，而在catch块中这是

ServiceEventSource.Current.ServiceMessage(serviceContext, $"Exception: " + JsonConvert.SerializeObject(ex));

出现以下错误：＆＃34; ServiceEventSource错误CS0103：名称＆＃39; ServiceEventSource＆＃39;在当前上下文中不存在＆＃34;？

谢谢！

Answer 1

解决

分析被调用方法的签名和代码，我们注意到一件事：

public void ServiceMessage(ServiceContext serviceContext, string message, params objects[] args)

这意味着message参数用于string.Format方法。

我的问题是传递带有“{”和“}”字符的Json字符串会引发异常，因为它无法识别格式。