问题描述
我正在使用ninject作为依赖项注入器在webapi中工作.我所有的构造函数注入对于我的控制器都工作正常.
I am working in webapi with ninject as dependency injector. All my constructor injection working fine for my controllers.
我有一个自定义的媒体类型格式化程序,该格式程序用于在用户请求"application/pdf"时返回pdf
I have custom mediatype formatter which used to return pdf when user requested for 'application/pdf'
在这里,我需要在创建pdf后更新数据.因此,在这里我需要致电我的业务类以更新数据.
Here i need to update data after create pdf. So here i need to call my business class to update data.
MyCustomFormatter代码:
public class PdfMediaTypeFormatter : MediaTypeFormatter
{
private readonly string mediaType = "application/pdf";
Func<Type, bool> typeisIPdf = (type) => typeof(IPdf).IsAssignableFrom(type);
Func<Type, bool> typeisIPdfCollection = (type) => typeof(IEnumerable<IPdf>).
IsAssignableFrom(type);
public PdfMediaTypeFormatter()
{
SupportedMediaTypes.Add(new MediaTypeHeaderValue(mediaType));
MediaTypeMappings.Add(new UriPathExtensionMapping("pdf", new MediaTypeHeaderValue(mediaType)));
}
public override bool CanReadType(Type type)
{
return false;
}
public override bool CanWriteType(Type type)
{
return typeisIPdf(type) || typeisIPdfCollection(type);
}
public async override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext)
{
var pdfData= new SamplePdf();
var memoryStream = report.Create(value);
var bytes = memoryStream.ToArray();
await writeStream.WriteAsync(bytes, 0, bytes.Length);
}
}
我的SamplePdf类代码:
public class SamplePdf
{
private readonly IBusinessLogic _logic;
public MemoryStream Create(object model)
{
//Pdf generation code
// here i need to call data update
//_logic.update(model);
}
}
我需要在业务类中插入_logic
字段.我已经在ninject配置中映射了相同的内容,如下所示;
I need to inject _logic
field with my business class. I already mapped the same in ninject configuration like below;
kernel.Bind<IBusinessLogic>().To<MyBusinessLogic>().InRequestScope();
如何将其注入我的班级?
How to inject this to my class?
推荐答案
基于提供的示例进行了以下假设.
With the following assumptions made based on the provided example.
public class PdfMediaTypeFormatter : MediaTypeFormatter {
private readonly string mediaType = "application/pdf";
Func<Type, bool> typeisIPdf = (type) => typeof(IPdf).IsAssignableFrom(type);
Func<Type, bool> typeisIPdfCollection = (type) => typeof(IEnumerable<IPdf>).
IsAssignableFrom(type);
private readonly IPdfFactory report;
public PdfMediaTypeFormatter(IPdfFactory report) {
SupportedMediaTypes.Add(new MediaTypeHeaderValue(mediaType));
MediaTypeMappings.Add(new UriPathExtensionMapping("pdf", new MediaTypeHeaderValue(mediaType)));
this.report = report;
}
public override bool CanReadType(Type type) {
return false;
}
public override bool CanWriteType(Type type) {
return typeisIPdf(type) || typeisIPdfCollection(type);
}
public async override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext) {
var memoryStream = report.Create(value);
var bytes = memoryStream.ToArray();
await writeStream.WriteAsync(bytes, 0, bytes.Length);
}
}
public interface IPdfFactory {
MemoryStream Create(object model);
}
public class PdfFactory : IPdfFactory {
private readonly IBusinessLogic _logic;
public PdfFactory(IBusinessLogic logic) {
this._logic = logic;
}
public MemoryStream Create(object model) {
var stream = new MemoryStream();
//...Pdf generation code
//call data update
_logic.update(model);
return stream;
}
}
注册将使用DI容器解析格式程序
Registration would use the DI container to resolve formatter
public static class WebApiConfig {
public static void Register(HttpConfiguration config) {
//...DI configuration
var formatter = (PdfMediaTypeFormatter)config.DependencyResolver.GetService(typeof(PdfMediaTypeFormatter));
config.Formatters.Add(formatter);
}
}
假设
kernel.Bind<IBusinessLogic>().To<MyBusinessLogic>();
kernel.Bind<IPdfFactory>().To<PdfFactory>();
kernel.Bind<PdfMediaTypeFormatter>().ToSelf();
这篇关于依赖注入到CustomFormatter的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!