在web api asp.net中返回值
本文关键字:返回值 net asp web api | 更新日期: 2023-09-27 18:20:08
我有两个代码:
第一个代码:
public class CategoryController : ApiController
{
Shop_DTBEntities shop_DTBEntities = new Shop_DTBEntities();
public IEnumerable<Category> GetAll_Category()
{
return shop_DTBEntities.Categories.ToList<Category>();
}
}
当我运行上面的代码时,它抛出了1个错误The 'ObjectContent
1`type未能序列化内容类型application/json的响应体;charset=utf-8'。"之后,我在global.asax中添加了新的2行代码:
protected void Application_Start()
{
GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
GlobalConfiguration.Configuration.Formatters.Remove(GlobalConfiguration.Configuration.Formatters.XmlFormatter);
GlobalConfiguration.Configure(WebApiConfig.Register);
}
但如果应用程序使用第二个代码,则会像上面的一样抛出错误
第二个代码:
public IEnumerable<Category> GetAll_Category()
{
using (Shop_DTBEntities shop_DTBEntities = new Shop_DTBEntities())
{
return shop_DTBEntities.Categories.ToList<Category>();
}
}
您可以通过一个配置设置来修复它
最好在dbcontext构造函数中使用它
public DbContext() // dbcontext constructor
: base("name=ConnectionStringNameFromWebConfig")
{
this.Configuration.LazyLoadingEnabled = false;
this.Configuration.ProxyCreationEnabled = false;
}