Retrieve required string from bigger JSON string

问题

I have JSON string returned by method:

public List<Issues> Getdata(
        string jql,
        List<string> fields = null,
        int startAt = 0,
        int maxResult = 500)
    {
        string data = JsonConvert.SerializeObject(request);
        string result = runQuery(JiraResource.search, data, "POST"); //returns results and working fine
        SearchResponse response = JsonConvert.DeserializeObject<SearchResponse>(result);
        return response.IssueDescriptions = GetIssues(response);;
    }

and JSON string look like this:

{"expand":"schema,names","startAt":0,"maxResults":50,"total":139,"issues":[{"expand":"operations,versionedRepresentations,editmeta,changelog,transitions,renderedFields","id":"20930","self":"https://clientname.atlassian.net/rest/api/2/issue/20930","key":"-139","fields":{"summary":"Rebate","issuetype":{"self":"https://clientname.atlassian.net/rest/api/2/issuetype/1","id":"1","description":"A fee negotiation or quote","iconUrl":"https://clientname.atlassian.net/images/icons/issuetypes/sales.png","name":"Fees","subtask":false},"components":[],"created":"2015-07-10T12:29:05.000+1000","description":"Execute as per attached instruction","project":{"self":"https://clientname.atlassian.net/rest/api/2/project/10013","id":"10013","key":"--","name":"Change Instructions","avatarUrls":{"48x48":"https://clientname.atlassian.net/secure/projectavatar?avatarId=10011","24x24":"https://clientname.atlassian.net/secure/projectavatar?size=small&avatarId=10011","16x16":"https://clientname.atlassian.net/secure/projectavatar?size=xsmall&avatarId=10011","32x32":"https://clientname.atlassian.net/secure/projectavatar?size=medium&avatarId=10011"}},"reporter":{"self":"https://clientname.atlassian.net/rest/api/2/user?username=rajap","name":"rajap","key":"rajap","emailAddress":"email.au","avatarUrls":{"48x48":"https://clientname.atlassian.net/secure/useravatar?avatarId=10142","24x24":"https://clientname.atlassian.net/secure/useravatar?size=small&avatarId=10142","16x16":"https://clientname.atlassian.net/secure/useravatar?size=xsmall&avatarId=10142","32x32":"https://clientname.atlassian.net/secure/useravatar?size=medium&avatarId=10142"},"displayName":"Prabu","active":true,"timeZone":"US"},"priority":{"self":"https://clientname.atlassian.net/rest/api/2/priority/3","iconUrl":"https://clientname.atlassian.net/images/icons/priorities/major.png","name":"Medium","id":"3"},"resolution":null,"duedate":"2015-07-15","comment":{"startAt":0,"maxResults":1,"total":1,"comments":[{"self":"https://clientname.atlassian.net/rest/api/2/issue/20930/comment/24290","id":"24290","author":{"self":"https://clientname.atlassian.net/rest/api/2/user?username=acahill","name":"acahill","key":"acahill","emailAddress":"email","avatarUrls":{"48x48":"https://clientname.atlassian.net/secure/useravatar?avatarId=10142","24x24":"https://clientname.atlassian.net/secure/useravatar?size=small&avatarId=10142","16x16":"https://clientname.atlassian.net/secure/useravatar?size=xsmall&avatarId=10142","32x32":"https://clientname.atlassian.net/secure/useravatar?size=medium&avatarId=10142"},"displayName":"Andrew Cahill","active":true,"timeZone":"US"},"body":"John, please action","updateAuthor":{"self":"https://clientname.atlassian.net/rest/api/2/user?username=acahill","name":"acahill","key":"acahill","emailAddress":"email","avatarUrls":{"48x48":"https://clientname.atlassian.net/secure/useravatar?avatarId=10142","24x24":"https://clientname.atlassian.net/secure/useravatar?size=small&avatarId=10142","16x16":"https://clientname.atlassian.net/secure/useravatar?size=xsmall&avatarId=10142","32x32":"https://clientname.atlassian.net/secure/useravatar?size=medium&avatarId=10142"},"displayName":"Andrew","active":true,"timeZone":"US"},"created":"2015-07-10T12:35:43.728+1000","updated":"2015-07-10T12:35:43.728+1000"}]},"votes":{"self":"https://clientname.atlassian.net/rest/api/2/issue/-139/votes","votes":0,"hasVoted":false},"assignee":{"self":"https://clientname.atlassian.net/rest/api/2/user?username=olearyj","name":"olearyj","key":"olearyj","emailAddress":"email","avatarUrls":{"48x48":"https://clientname.atlassian.net/secure/useravatar?avatarId=10142","24x24":"https://clientname.atlassian.net/secure/useravatar?size=small&avatarId=10142","16x16":"https://clientname.atlassian.net/secure/useravatar?size=xsmall&avatarId=10142","32x32":"https://clientname.atlassian.net/secure/useravatar?size=medium&avatarId=10142"},"displayName":"John","active":true,"timeZone":"US"},"status":{"self":"https://clientname.atlassian.net/rest/api/2/status/1","description":"The issue is open and ready for the assignee to start work on it.","iconUrl":"https://clientname.atlassian.net/images/icons/statuses/open.png","name":"Open","id":"1","statusCategory":{"self":"https://clientname.atlassian.net/rest/api/2/statuscategory/2","id":2,"key":"new","colorName":"blue-gray","name":"To Do"}}}}]}

I wanted parser method for the above json string to get particular values of these field values like :

"summary", "status", "assignee", "comments", "description", "created", "duedate", "environment", "priority", "project", "reporter", "resolution", "issuetype", "Updated", "votes", "components"

I tried to get one by one.however, its complex and time taking.

This is how I'm trying. But error: Object reference not set to an instance of an object.

private List<JiraIssues> GetIssues(SearchResponse response)
{
    List<JiraIssues> returnResulttoReport = new List<JiraIssues>();
    foreach (var item in response.IssueDescriptions) //error here (not sure why IssueDescriptions is NULL but before call i'm de-serializing it)
    {
        foreach (var item1 in item.Comments)
        {

        }
    }

    return returnResulttoReport; 
}

My return type is List<Issuees>. Is there any library or example link to do this?

Please note that, I'm already de-serializing it, now I wanted perticular list from that.Also, please note that the JSON full string I have given is not same as the actual I have.But its similar. Please guide.

回答1:

Use something like json2csharp to generate C# classes for the json, to prevent errors. Then do something like

var result = JsonConvert.DeserializeObject<RootObject>(myJsonString);

EDIT
Here is an example of how to get the summaries:

RootObject result = JsonConvert.DeserializeObject<RootObject>(json);

List<string> summaries = new List<string>();
foreach (var item in result.issues)
{
    var summary = item.fields.summary;
    Console.WriteLine(summary);
    summaries.Add(summary);
}

RootObject will represent the top level object of your JSON and then it will have properties which correspond to each of the properties of your JSON.

回答2:

you can try like this :

    public class Issuetype
    {
        public string self { get; set; }
        public string id { get; set; }
        public string description { get; set; }
        public string iconUrl { get; set; }
        public string name { get; set; }
        public bool subtask { get; set; }
    }

    public class AvatarUrls
    {
        public string __invalid_name__48x48 { get; set; }
        public string __invalid_name__24x24 { get; set; }
        public string __invalid_name__16x16 { get; set; }
        public string __invalid_name__32x32 { get; set; }
    }

    public class Project
    {
        public string self { get; set; }
        public string id { get; set; }
        public string key { get; set; }
        public string name { get; set; }
        public AvatarUrls avatarUrls { get; set; }
    }

    public class AvatarUrls2
    {
        public string __invalid_name__48x48 { get; set; }
        public string __invalid_name__24x24 { get; set; }
        public string __invalid_name__16x16 { get; set; }
        public string __invalid_name__32x32 { get; set; }
    }

    public class Reporter
    {
        public string self { get; set; }
        public string name { get; set; }
        public string key { get; set; }
        public string emailAddress { get; set; }
        public AvatarUrls2 avatarUrls { get; set; }
        public string displayName { get; set; }
        public bool active { get; set; }
        public string timeZone { get; set; }
    }

    public class Priority
    {
        public string self { get; set; }
        public string iconUrl { get; set; }
        public string name { get; set; }
        public string id { get; set; }
    }

    public class AvatarUrls3
    {
        public string __invalid_name__48x48 { get; set; }
        public string __invalid_name__24x24 { get; set; }
        public string __invalid_name__16x16 { get; set; }
        public string __invalid_name__32x32 { get; set; }
    }

    public class Author
    {
        public string self { get; set; }
        public string name { get; set; }
        public string key { get; set; }
        public string emailAddress { get; set; }
        public AvatarUrls3 avatarUrls { get; set; }
        public string displayName { get; set; }
        public bool active { get; set; }
        public string timeZone { get; set; }
    }

    public class AvatarUrls4
    {
        public string __invalid_name__48x48 { get; set; }
        public string __invalid_name__24x24 { get; set; }
        public string __invalid_name__16x16 { get; set; }
        public string __invalid_name__32x32 { get; set; }
    }

    public class UpdateAuthor
    {
        public string self { get; set; }
        public string name { get; set; }
        public string key { get; set; }
        public string emailAddress { get; set; }
        public AvatarUrls4 avatarUrls { get; set; }
        public string displayName { get; set; }
        public bool active { get; set; }
        public string timeZone { get; set; }
    }

    public class Comment2
    {
        public string self { get; set; }
        public string id { get; set; }
        public Author author { get; set; }
        public string body { get; set; }
        public UpdateAuthor updateAuthor { get; set; }
        public string created { get; set; }
        public string updated { get; set; }
    }

    public class Comment
    {
        public int startAt { get; set; }
        public int maxResults { get; set; }
        public int total { get; set; }
        public List<Comment2> comments { get; set; }
    }

    public class Votes
    {
        public string self { get; set; }
        public int votes { get; set; }
        public bool hasVoted { get; set; }
    }

    public class AvatarUrls5
    {
        public string __invalid_name__48x48 { get; set; }
        public string __invalid_name__24x24 { get; set; }
        public string __invalid_name__16x16 { get; set; }
        public string __invalid_name__32x32 { get; set; }
    }

    public class Assignee
    {
        public string self { get; set; }
        public string name { get; set; }
        public string key { get; set; }
        public string emailAddress { get; set; }
        public AvatarUrls5 avatarUrls { get; set; }
        public string displayName { get; set; }
        public bool active { get; set; }
        public string timeZone { get; set; }
    }

    public class StatusCategory
    {
        public string self { get; set; }
        public int id { get; set; }
        public string key { get; set; }
        public string colorName { get; set; }
        public string name { get; set; }
    }

    public class Status
    {
        public string self { get; set; }
        public string description { get; set; }
        public string iconUrl { get; set; }
        public string name { get; set; }
        public string id { get; set; }
        public StatusCategory statusCategory { get; set; }
    }

    public class Fields
    {
        public string summary { get; set; }
        public Issuetype issuetype { get; set; }
        public List<object> components { get; set; }
        public string created { get; set; }
        public string description { get; set; }
        public Project project { get; set; }
        public Reporter reporter { get; set; }
        public Priority priority { get; set; }
        public object resolution { get; set; }
        public string duedate { get; set; }
        public Comment comment { get; set; }
        public Votes votes { get; set; }
        public Assignee assignee { get; set; }
        public Status status { get; set; }
    }

    public class Issue
    {
        public string expand { get; set; }
        public string id { get; set; }
        public string self { get; set; }
        public string key { get; set; }
        public Fields fields { get; set; }
    }

    public class RootObject
    {
        public string expand { get; set; }
        public int startAt { get; set; }
        public int maxResults { get; set; }
        public int total { get; set; }
        public List<Issue> issues { get; set; }
    }

var t = JsonConvert.DeserializeObject<RootObject>(json);
var issues = t.issues;

来源：https://stackoverflow.com/questions/31531441/retrieve-required-string-from-bigger-json-string