反序列化json数据使用c获取图像＃

Question

我在wikipedia api上发出请求以获得3图像url，以便我可以在我的代码中使用此图片。我使用url https://en.wikipedia.org/w/api.php?action=query&prop=imageinfo&format=json&iiprop=url&iiurlwidth=400&titles=File%3ALuftbild%20Flensburg%20Schleswig-Holstein%20Zentrum%20Stadthafen%20Foto%202012%20Wolfgang%20Pehlemann%20Steinberg-Ostsee%20IMG%206187.jpg%7CFile%3AHafen%20St%20Marien%20Flensburg2007.jpg%7CFile%3ANordertor%20im%20Schnee%20(Flensburg%2C%20Januar%202014).JPG来获得三张图片。我从json2csharp获得了json文件。

  public class Imageinfo 
     { 
      public string thumburl { get; set; } 
      public int thumbwidth { get; set; } 
      public int thumbheight { get; set; } 
      public string url { get; set; } 
      public string descriptionurl { get; set; } 
     } 

     public class Pageval1 
     { 
      public int ns { get; set; } 
      public string title { get; set; } 
      public string missing { get; set; } 
      public string imagerepository { get; set; } 
      public List<Imageinfo> imageinfo { get; set; } 
     } 

     public class Imageinfo2 
     { 
      public string thumburl { get; set; } 
      public int thumbwidth { get; set; } 
      public int thumbheight { get; set; } 
      public string url { get; set; } 
      public string descriptionurl { get; set; } 
     } 

     public class Pageval2 
     { 
      public int ns { get; set; } 
      public string title { get; set; } 
      public string missing { get; set; } 
      public string imagerepository { get; set; } 
      public List<Imageinfo2> imageinfo { get; set; } 
     } 

     public class Imageinfo3 
     { 
      public string thumburl { get; set; } 
      public int thumbwidth { get; set; } 
      public int thumbheight { get; set; } 
      public string url { get; set; } 
      public string descriptionurl { get; set; } 
     } 

     public class Pageval3 
     { 
      public int ns { get; set; } 
      public string title { get; set; } 
      public string missing { get; set; } 
      public string imagerepository { get; set; } 
      public List<Imageinfo3> imageinfo { get; set; } 
     } 

     public class Pages 
    { 
     public List<Pageval1> pageval1 { get; set; } 
     public List<Pageval2> pageval2 { get; set; } 
     public List<Pageval3> pageval3 { get; set; } 
    } 


class Image 
{ 
    public static PictureBox Image1 = new PictureBox(); 
    public static PictureBox Image2 = new PictureBox(); 
    public static PictureBox Image3 = new PictureBox(); 

    public static void Load_Image1() 
    { 
     using (WebClient wc = new WebClient()) 
     { 
     var client = new WebClient(); 
     var uri = ("https://en.wikipedia.org/w/api.php?action=query&prop=imageinfo&format=json&iiprop=url&iiurlwidth=400&titles=File%3ALuftbild%20Flensburg%20Schleswig-Holstein%20Zentrum%20Stadthafen%20Foto%202012%20Wolfgang%20Pehlemann%20Steinberg-Ostsee%20IMG%206187.jpg%7CFile%3AHafen%20St%20Marien%20Flensburg2007.jpg%7CFile%3ANordertor%20im%20Schnee%20(Flensburg%2C%20Januar%202014).JPG"); 
     var response = client.DownloadString(new Uri(uri)); 

     var responseJson = JsonConvert.DeserializeObject<RootObject>(response); 
     var firstKey1 = responseJson.query.pages.First().Key; 
     string image1 = responseJson.query.pages[firstKey1].pageval1.First().imageinfo.First().thumburl; 

     String image2 = responseJson.query.pages[firstKey1].pageval2.First().imageinfo.First().thumburl; 
     String image3 = responseJson.query.pages[firstKey1].pageval3.First().imageinfo.First().thumburl; 

     Image1.SizeMode = PictureBoxSizeMode.StretchImage; 
     Image2.SizeMode = PictureBoxSizeMode.StretchImage; 
     Image3.SizeMode = PictureBoxSizeMode.StretchImage; 
     Image1.LoadAsync(image1); 
     Image2.LoadAsync(image2); 
     Image3.LoadAsync(image3); 




     } 
    } 
    } 


} 

我想从每个imageinfo获取缩略图。但我不知道如何处理这些类来序列化json然后获取图像。

Answer 1

我认为你正在努力的是如何处理这些无效的类。那么发生的问题是，-1，-2，-3作为C＃标识符无效，因此无法为这些项目创建类。

因为这种情况下他们需要动态我们可以通过使用pages元素的字典来解决此问题。

注意我正在使用Json.Net所以你会想要通过Nuget安装。

string url = @"https://en.wikipedia.org/w/api.php?action=query&prop=imageinfo&format=json&iiprop=url&iiurlwidth=400&titles=File%3ALuftbild%20Flensburg%20Schleswig-Holstein%20Zentrum%20Stadthafen%20Foto%202012%20Wolfgang%20Pehlemann%20Steinberg-Ostsee%20IMG%206187.jpg|File%3AHafen%20St%20Marien%20Flensburg2007.jpg|File%3ANordertor%20im%20Schnee%20%28Flensburg%2C%20Januar%202014%29.JPG"; 

// i'll leave it up to you to do any null and error checking 
using (var client = new WebClient()) 
{ 
    var text = client.DownloadString(url); 
    var result = JsonConvert.DeserializeObject<RootObject>(text); 

    foreach (var page in result.Query.Pages) 
    { 
     foreach (var imageInfo in page.Value.ImageInfo) 
     { 
      Console.WriteLine("{0}: {1}", page.Value.Title, imageInfo.ThumbUrl); 
     } 
    } 
} 

// the relevant classes for deserialization 

public class RootObject 
{ 
    public string BatchComplete { get; set; } 
    public Query Query { get; set; } 
} 

public class Query 
{ 
    // this is how you can deal with those invalid identifiers 
    // the -1, -2, -3 will be placed as keys inside this dictionary 
    public Dictionary<string, Page> Pages { set; get; } 
} 

public class Page 
{ 
    public int Ns { get; set; } 
    public string Title { get; set; } 
    public string Missing { get; set; } 
    public string ImageRepository { get; set; } 
    public List<ImageInfo> ImageInfo { get; set; } 
} 

public class ImageInfo 
{ 
    public string ThumbUrl { get; set; } 
    public int ThumbWidth { get; set; } 
    public int ThumbHeight { get; set; } 
    public string Url { get; set; } 
    public string DescriptionUrl { get; set; } 
} 

输出将是：

File:Luftbild Flensburg Schleswig-Holstein Zentrum Stadthafen Foto 2012 Wolfgang Pehlemann Steinberg-Ostsee IMG 6187.jpg: https://upload.wikimedia.org/wikipedia/commons/thumb/a/ae/Luftbild_Flensburg_Schleswig-Holstein_Zentrum_Stadthafen_Foto_2012_Wolfgang_Pehlemann_Steinberg-Ostsee_IMG_6187.jpg/400px-Luftbild_Flensburg_Schleswig-Holstein_Zentrum_Stadthafen_Foto_2012_Wolfgang_Pehlemann_Steinberg-Ostsee_IMG_6187.jpg 
File:Hafen St Marien Flensburg2007.jpg: https://upload.wikimedia.org/wikipedia/commons/thumb/a/a8/Hafen_St_Marien_Flensburg2007.jpg/400px-Hafen_St_Marien_Flensburg2007.jpg 
File:Nordertor im Schnee (Flensburg, Januar 2014).JPG: https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Nordertor_im_Schnee_%28Flensburg%2C_Januar_2014%29.JPG/400px-Nordertor_im_Schnee_%28Flensburg%2C_Januar_2014%29.JPG