Parse JSON result and check for specifing string in status

Question

What is the most efficient apprach to read such JSON file. To be honest what i need to take from that JSON is the distance. Inside elements node there could be either one or multiple items containing distance and duration. I need to SUM all of that values from each element's node: distance-text. For example: 324 km (distance in kilemeters). I shown below 3 examples. How can i do that?

Morover in last example if request is bad there could be something like "NOT_FOUND" (or something else besides "OK"). If in any "status" there would be something diffrent than "OK" at east in one i should get throw Exception().

JSON response example 1:

{
   "destination_addresses" : [ "Długa 50, 05-075 Warszawa, Slovakia" ],
   "origin_addresses" : [ "Wilenska 2, Zabrze, Slovakia" ],
   "rows" : [
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "324 km",
                  "value" : 323619
               },
               "duration" : {
                  "text" : "3 hours 16 mins",
                  "value" : 11776
               },
               "status" : "OK"
            }
         ]
      }
   ],
   "status" : "OK"
}

In this case i should calculate as: 324

JSON response example 2: (There could be more elements like here)

{
   "destination_addresses" : [ "Długa 50, 05-075 Warszawa, Slovakia" ],
   "origin_addresses" : [ "Wilenska 2, Zabrze, Slovakia" ],
   "rows" : [
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "324 km",
                  "value" : 323619
               },
               "duration" : {
                  "text" : "3 hours 16 mins",
                  "value" : 11776
               },
               "status" : "OK"
            },
            {
               "distance" : {
                  "text" : "192 km",
                  "value" : 191950
               },
               "duration" : {
                  "text" : "2 hours 26 mins",
                  "value" : 8732
               },
               "status" : "OK"
            },
         ]
      }
   ],
   "status" : "OK"
}

In this case i should calculate as: 516

JSON response example 3: (with some statuses diffrent than "OK")

{
   "destination_addresses" : [ "", "", "" ],
   "origin_addresses" : [ "" ],
   "rows" : [
      {
         "elements" : [
            {
               "status" : "NOT_FOUND"
            },
            {
               "status" : "OK"
            },
            {
               "status" : "NOT_FOUND"
            }
         ]
      }
   ],
   "status" : "ERR" 
}

In this case i should get Exception

Q: I'm curious: why "Slovakia", and not "Poland"? To answer your question: you *DON'T* want to "check for a string". You want to add Json.Net (a NuGet package) to your project, and call `JsonConvert.Deserialize()`: https://www.hanselman.com/blog/NuGetPackageOfTheWeek4DeserializingJSONWithJsonNET.aspx — paulsm4, Sep 06 '20 at 20:41
@paulsm4 I have some generator for other purposes but it's not the case for that topic. — Arie, Sep 06 '20 at 21:08
Use NewtonSoft library. You can call JsonConvert.DeserializeObject(). It would create an object of your JSON that you can loop through a foreach. Then just add up each "distance" from this object to a new variable if the status is "OK", otherwise throw an Exception. — thomashoareau, Sep 06 '20 at 21:11
@ThomasH can you post the answer? Don;t know how to get those values (still trying) — Arie, Sep 06 '20 at 23:05

score 2 · Accepted Answer · answered Sep 07 '20 at 01:40

you can use https://json2csharp.com/ to generate C# classes based on your json structure.

then install nuget package https://www.nuget.org/packages/Json.Net/

then you can try the following code:

var sampleJson = @"{


""destination_addresses"" : [ ""Długa 50, 05-075 Warszawa, Slovakia"" ],
   ""origin_addresses"" : [ ""Wilenska 2, Zabrze, Slovakia"" ],
   ""rows"" : [
      {
         ""elements"" : [
            {
               ""distance"" : {
                  ""text"" : ""324 km"",
                  ""value"" : 323619
               },
               ""duration"" : {
                  ""text"" : ""3 hours 16 mins"",
                  ""value"" : 11776
               },
               ""status"" : ""OK""
            },
            {
               ""distance"" : {
                  ""text"" : ""192 km"",
                  ""value"" : 191950
               },
               ""duration"" : {
                  ""text"" : ""2 hours 26 mins"",
                  ""value"" : 8732
               },
               ""status"" : ""OK""
            },
         ]
      }
   ],
   ""status"" : ""OK""
}";

    var obj = Newtonsoft.Json.JsonConvert.DeserializeObject<Root>(sampleJson);
    if (obj.status != "OK")
    {
        throw new Exception($"Status is: {obj.status}");
    }

    if (obj.rows.Any(r => r.elements.Any(e => e.status != "OK")))
    {
        throw new Exception("some of the elements status is not ok");
    }

    var allDistanceText = obj.rows?.Select(e => e.elements).SelectMany(e => e.Select(d => d.distance?.text));
    int sum = allDistanceText.Select(dt => dt?.Replace("km", "")?.Trim())
        .Sum(dt =>
        {
            if (int.TryParse(dt, out int results))
            {
                return results;
            }
            return 0;
        });
    sum.Dump();

I get null on var obj = Newtonsoft.Json.JsonConvert.DeserializeObject(jsonstring); I provided from my examples. — Arie, Sep 07 '20 at 09:05

Parse JSON result and check for specifing string in status

1 Answers1