反序列化为double时，JsonConvert会抛出一个“非有效整数”异常

Question

I get an exception when I try to deserialize to an object from a JSON string.

Input string '46.605' is not a valid integer. Path 'LatitudeCenter'

It's really weird because JsonConvert tries to deserialize an attribute as an integer but it actually is a double and not an integer .

I already checked in my Web API project. The attribute in my class is a double and same in web project.

The code I use in my web asp project:

using (var client = new HttpClient())
{
    client.BaseAddress = new Uri("myWebApiHostedUrl");
    client.DefaultRequestHeaders.Accept.Clear();
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

    // Get the response
    HttpResponseMessage response = await client.GetAsync("api/NewMap/?SouthLatitude=46.600&WestLongitude=7.085&NorthLatitude=46.610&EastLongitude=7.095&Width=900&Height=900&isVoxelMap=true");
    string jsonData = response.Content.ReadAsStringAsync().Result;

    //Exception here
    NewMap dataMewMap = JsonConvert.DeserializeObject<NewMap>(jsonData, new JsonSerializerSettings() { Culture = CultureInfo.InvariantCulture,FloatParseHandling= FloatParseHandling.Double });
}

Here is my class:

public class NewMap
{
    // ...
    public double LatitudeCenter { get; set; }
    public double LongitudeCenter { get; set; }
    // ...
}

My JSON content:

{
    // ...
    "LatitudeCenter":46.605,
    "LongitudeCenter":7.09,
    "SouthLatitude":46.6,
    "ImageBingUrl":null,
    "PercentEnvironement_Plain":0,
    // ...
}

Answer 1

It could very well be because your regional settings use something other than a 'dot' to represent what's after the integer part of a double , such as the fr-FR culture.

A rough guess is that the JsonConvert class uses methods for parsing numbers from .NET (there's no reason why it wouldn't after all), such as Double.TryParse . And these very method do by default, take into account your current culture .

Try setting the culture of JsonConvert to CultureInfo.InvariantCulture .