c#之如何在 Windows Phone 7 中为 JSON Web 服务结果创建类

如何为 JSON Web 服务结果创建类？这是我从 google api 获得的 JSON 结果。那么，如何为这个 JSON 对象创建类和反序列化。

我创建了一个类来反序列化这个 JSON 对象，

string mapdetail = e.Result; 
        var djosn = new DataContractJsonSerializer(typeof(mapResult)); 
        var mstr = new MemoryStream(Encoding.UTF8.GetBytes(mapdetail)); 
        mapResult reslt = (mapResult)djosn.ReadObject(mstr); 

map 结果类:

[DataContract] 
public class mapResult 
{ 
    [DataMember] 
    public string status 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public IList<Resultdetail> result 
    { 
        get; 
        set; 
    } 
} 

所以我创建了结果详细信息和其他列表:

[DataContract] 
public class Resultdetail 
{ 
    [DataMember] 
    public List<string> types 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public string formatted_address 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public List<object> address_components 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public List<Geometry> geometry 
    { 
        get; 
        set; 
    } 
 
} 
 
[DataContract] 
public class Geometry 
{ 
    [DataMember] 
    public List<GeoLocation> location 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public string location_type 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public List<object> viewport 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public List<object> bounds 
    { 
        get; 
        set; 
    } 
 
} 
 
[DataContract] 
public class GeoLocation 
{ 
    [DataMember] 
    public double lat 
    { 
        get; 
        set; 
    } 
    [DataMember] 
    public double lng 
    { 
        get; 
        set; 
    } 
 
} 

现在我得到的是 Null 引用；

请您参考如下方法:

您的 DatContract 类存在一些问题。

我在下面更正了这些内容，注释掉了原始行并添加了关于具体错误的评论。

[DataContract] 
public class mapResult 
{ 
    [DataMember] 
    public string status { get; set; } 
    [DataMember] 
    //public IList<Resultdetail> result { get; set; } 
    // Misspelt property name and use of interface rather than concrete type 
    public List<Resultdetail> results { get; set; } 
} 
 
[DataContract] 
public class Resultdetail 
{ 
    [DataMember] 
    public List<string> types { get; set; } 
    [DataMember] 
    public string formatted_address { get; set; } 
    [DataMember] 
    public List<object> address_components { get; set; } 
    [DataMember] 
    //public List<Geometry> geometry { get; set; } 
    // Json does not contain an array/list of these 
    public Geometry geometry { get; set; } 
} 
 
[DataContract] 
public class Geometry 
{ 
    [DataMember] 
    //public List<GeoLocation> location { get; set; } 
    // Json does not contain an array/list of these 
    public GeoLocation location { get; set; } 
    [DataMember] 
    public string location_type { get; set; } 
    [DataMember] 
    // public List<object> viewport { get; set; }   
    // Json does not contain an array/list of these 
    public object viewport { get; set; } 
    [DataMember] 
    //public List<object> bounds { get; set; } 
    // Json does not contain an array/list of these 
    public object bounds { get; set; } 
} 

下面的代码表明这是可行的:

var jsonStr = "{\"status\": \"OK\", \"results\": [ { \"types\": [ \"route\" ], \"formatted_address\": \"7th Main Rd, Koramangala, sengaluru, Karnataka 560034, India\", \"address_components\": [ { \"long_name\": \"7th Main Rd\", \"short_name\": \"7th Main Rd\", \"types\": [ \"route\" ] }, { \"long_name\": \"Koramangala\", \"short_name\": \"Koramangala\", \"types\": [ \"sublocality\", \"political\" ] }, { \"long_name\": \"Bengaluru\", \"short_name\": \"Bengaluru\", \"types\": [ \"locality\", \"political\" ] }, { \"long_name\": \"sengaluru\", \"short_name\": \"sengaluru\", \"types\": [ \"administrative_area_level_2\", \"political\" ] }, { \"long_name\": \"Karnataka\", \"short_name\": \"Karnataka\", \"types\": [ \"administrative_area_level_1\", \"political\" ] }, { \"long_name\": \"India\", \"short_name\": \"IN\", \"types\": [ \"country\", \"political\" ] }, { \"long_name\": \"560034\", \"short_name\": \"560034\", \"types\": [ \"postal_code\" ] }],\"geometry\": { \"location\":{ \"lat\": 12.9259085, \"lng\": 77.6334715 }, \"location_type\": \"GEOMETRIC_CENTER\", \"viewport\": { \"southwest\": { \"lat\": 12.9227118, \"lng\": 77.6301852 }, \"northeast\": { \"lat\": 12.929007, \"lng\": 77.6364805}}, \"bounds\": { \"southwest\": { \"lat\": 12.9247615, \"lng\": 77.6330486 },\"northeast\": { \"lat\": 12.9269574, \"lng\": 77.6336171 }}}}]}"; 
 
// If using json.net (http://json.codeplex.com/) 
var des = JsonConvert.DeserializeObject<mapResult>(jsonStr); 
 
// If using System.Runtime.Serialization.Json 
var djosn = new DataContractJsonSerializer(typeof(mapResult)); 
var mstr = new MemoryStream(Encoding.UTF8.GetBytes(jsonStr)); 
des = (mapResult)djosn.ReadObject(mstr); 
 
var latitude = des.results[0].geometry.location.lat; 
var longitude = des.results[0].geometry.location.lng; 

请注意，我的代码仅使用您的示例 json 对象进行了测试，不能保证适用于网络服务返回的所有内容。您还对 object 进行了很多反序列化，如果您想要的不仅仅是纬度和经度，使用起来可能会很尴尬。