一、设置webapi返回json格式
在App_Start下的WebApiConfig的注册函数Register中添加下面这代码
config.Formatters.Remove(config.Formatters.XmlFormatter);
二、设置返回Json键值统一为小写
新建一个类并继承自DefaultContractResolver,重写ResolvePropertyName方法,
public class UnderlineSplitContractResolver : DefaultContractResolver
{
protected override string ResolvePropertyName(string propertyName)
{
//return CamelCaseToUnderlineSplit(propertyName);
return propertyName.ToLower();
}
}
在WebApiConfig.Register方法中添加配置代码
// 对 JSON 数据使用混合大小写。跟属性名同样的大小.输出
config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new UnderlineSplitContractResolver();
三、在返回的JSON格式中出现两个很不开心的问题
看图:
第一个问题是为null的字符串,这里也返回了null,感觉返回""感觉好一点
第二个问题,lastupdate是时间格式,这种格式化看着有点不爽,如果是"2016-03-25 17:19:17"感觉就好点了
解决如下:
在解决第二个问题时我们新建的类UnderlineSplitContractResolver里面重写CreateProperties方法:
//解决API NULL 和时间格式问题
protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)
{
return type.GetProperties
.Select(p =>
{
var jp = base.CreateProperty(p, memberSerialization);
if (jp.PropertyType == typeof(System.String))
jp.ValueProvider = new NullToEmptyStringValueProvider(p);
if (jp.PropertyType.ToString().Contains("System.DateTime"))
jp.Converter = new IsoDateTimeConverter() { DateTimeFormat = "yyyy-MM-dd HH:mm:ss" };
return jp;
}).ToList();
}
NullToEmptyStringValueProvider类继承IValueProvider,代码如下:
/// <summary>
/// 解决返回json数据null问题
/// </summary>
public class NullToEmptyStringValueProvider : IValueProvider
{
PropertyInfo _MemberInfo;
public NullToEmptyStringValueProvider(PropertyInfo memberInfo)
{
_MemberInfo = memberInfo;
}
public object GetValue(object target)
{
object result = _MemberInfo.GetValue(target);
//if (result == null)
// result = "";
if (_MemberInfo.PropertyType == typeof(string) && result == null)
result = "";
return result;
}
public void SetValue(object target, object value)
{
_MemberInfo.SetValue(target, value);
}
}
此时问题已经解决,返回的json如下:
看起来是不是舒服多了?
四、整理一下代码
新建一个文件InitAPI.cs,代码如下:
public class InitAPI
{
public static void Init(HttpConfiguration config)
{
//HttpConfiguration config = GlobalConfiguration.Configuration;
config.Formatters.Remove(config.Formatters.XmlFormatter); // 解决json序列化时的循环引用问题
config.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
// 对 JSON 数据使用混合大小写。驼峰式,但是是javascript 首字母小写形式.
//config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
// 对 JSON 数据使用混合大小写。跟属性名同样的大小.输出
config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new UnderlineSplitContractResolver();
}
} public class UnderlineSplitContractResolver : DefaultContractResolver
{ protected override string ResolvePropertyName(string propertyName)
{
//return CamelCaseToUnderlineSplit(propertyName);
return propertyName.ToLower();
}
private string CamelCaseToUnderlineSplit(string name)
{
return name.ToLower();
} //解决API NULL 和时间格式问题
protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)
{
return type.GetProperties()
.Select(p =>
{
var jp = base.CreateProperty(p, memberSerialization);
if (jp.PropertyType == typeof(System.String))
jp.ValueProvider = new NullToEmptyStringValueProvider(p);
if (jp.PropertyType.ToString().Contains("System.DateTime"))
jp.Converter = new IsoDateTimeConverter() { DateTimeFormat = "yyyy-MM-dd HH:mm:ss" };
return jp;
}).ToList();
} }
/// <summary>
/// 解决返回json数据null问题
/// </summary>
public class NullToEmptyStringValueProvider : IValueProvider
{
PropertyInfo _MemberInfo;
public NullToEmptyStringValueProvider(PropertyInfo memberInfo)
{
_MemberInfo = memberInfo;
}
public object GetValue(object target)
{
object result = _MemberInfo.GetValue(target);
//if (result == null)
// result = "";
if (_MemberInfo.PropertyType == typeof(string) && result == null)
result = "";
return result;
}
public void SetValue(object target, object value)
{
_MemberInfo.SetValue(target, value);
}
}
在WebApiConfig中直接调用InitAPI.Init(config),代码如下:
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// Web API 配置和服务 // Web API 路由
config.MapHttpAttributeRoutes(); config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
); InitAPI.Init(config);
}
}
结束