Question

我有一个Web-API，其中有许多函数可以将对象作为JSON返回，例如：

MyPython.py

如何实现错误处理？如果发生错误，我想返回一个JSON，只是说{＆＃34;错误＆＃34;：＆＃34;出错了＆＃34;}

现在，如果发生崩溃，API只会返回500错误。

Answer 1

您最好的选择是实施自定义ExceptionHandler

public class MyCustomExceptionHandler : ExceptionHandler
{
    private readonly HttpConfiguration _configuration;

    public MyCustomExceptionHandler(HttpConfiguration config){
        _configuration = config;
    }

    public override void Handle(ExceptionHandlerContext context)
    {
        var formatters = _configuration.Formatters;
        var negotiator = _configuration.Services.GetContentNegotiator();

        context.Result = new NegotiatedContentResult<ErrorResponse>(HttpStatusCode.InternalServerError, new ErrorResponse
            {
                Message = context.Exception.Message,
                CustomProperty = "Something"
            }, negotiator, context.Request, formatters);
    }

    public override bool ShouldHandle(ExceptionHandlerContext context)
    {
        return true; //your logic if you want only certain exception to be handled
    }
}

internal class ErrorResponse
{
    public string Message { get; set; }

    public string CustomProperty { get; set; }
}

并在WebApiConfig.cs文件中注册：

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        config.Services.Replace(typeof (IExceptionHandler), new MyCustomExceptionHandler(config));
        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{action}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

        var appXmlType = config.Formatters.XmlFormatter.SupportedMediaTypes.FirstOrDefault(t => t.MediaType == "application/xml");
        config.Formatters.XmlFormatter.SupportedMediaTypes.Remove(appXmlType);
    }
}

通过这种方式，您可以在未处理的异常情况下返回错误消息的精细分级自定义。

Web API错误handeling返回json

1 个答案: