使用Newtonsoft C＃读取Json字符串

Question

I cannot read json string with c#. I getting error while reading.

Json file

{
    "Invoice": {
        "Description": "New",
        "InvoiceTypeId": "3d166468-3923-11e6-9e7c-40e230cfb8ae",
        "CustomerAccountsId": "TEST",
        "InvoiceDate": "2016-06-27",
        "PayableDate": "2016-06-27",
        "Prefix": "A",
        "Serial": "34222",
        "tag": "TEST"
    },
    "InvoiceLine": [
        {
            "ValueId": "c41d3d85-3a1e-11e6-9e7c-40e230cfb8ae",
            "Qantity": "3",
            "UnitId": "a72e0dde-3953-11e6-9e7c-40e230cfb8ae",
            "Price": "1.500,00",
            "VatRateId": "18",
            "LineVat": "810,00",
            "LineTotal": "5.310,00",
            "Vat": "00a239f1-3c3a-11e6-9e7c-40e230cfb8ae"
        },
        {
            "ValueId": "fd11b236-3952-11e6-9e7c-40e230cfb8ae",
            "Qantity": "5",
            "UnitId": "a72e0dde-3953-11e6-9e7c-40e230cfb8ae",
            "Price": "1.000,00",
            "VatRateId": "18",
            "LineVat": "900,00",
            "LineTotal": "5.900,00",
            "Vat": "00a239f1-3c3a-11e6-9e7c-40e230cfb8ae"
        }
    ]
}

"Error reading JArray from JsonReader. Current JsonReader item is not an array: StartObject. Path '', line 1, position 1."

JArray jsonVal = JArray.Parse(jsonArr) as JArray;
dynamic vars = jsonVal;

But everything right, I do not see bugs.

Answer 1

Don't do this...you're parsing to an array when it's clearly a complex object.

Use a converter such as Visual Studio or json2csharp.com to create the appropriate target object structure:

public class Invoice
{
    public string Description { get; set; }
    public string InvoiceTypeId { get; set; }
    public string CustomerAccountsId { get; set; }
    public string InvoiceDate { get; set; }
    public string PayableDate { get; set; }
    public string Prefix { get; set; }
    public string Serial { get; set; }
    public string tag { get; set; }
}

public class InvoiceLine
{
    public string ValueId { get; set; }
    public string Qantity { get; set; }
    public string UnitId { get; set; }
    public string Price { get; set; }
    public string VatRateId { get; set; }
    public string LineVat { get; set; }
    public string LineTotal { get; set; }
    public string Vat { get; set; }
}

public class Invoices
{
    public Invoice Invoice { get; set; }
    public List<InvoiceLine> InvoiceLine { get; set; }
}

Then simply use the JsonConvert methods to deserialize.

var parsedJson = JsonConvert.DeserializeObject<Invoices>(json);

Answer 2

You can also deserialize it to a dynamic object. Of course this is not ideal but if you don't want to create a whole new type for it, this would work

var vars =JsonConvert.DeserializeObject<dynamic>(  jsonArr);
//vars.InvoiceLine

Answer 3

I noticed in the question and a comment you made, "How do I read this?" that you might also be confused on reading JSON which made the error message confusing to you.

You are trying to parse the object as a JArray while your JSON isn't for an array.

If you look at your error message,

"Error reading JArray from JsonReader. Current JsonReader item is not an array: StartObject. Path '', line 1, position 1."

It's immediately throwing an error at the first character on the first line of your JSON and telling you it's not an array.

{ is the first character of your JSON, it was an array than it should start with [ just like if you were writing JavaScript.

Array:

var javaScriptArray = ["This", "Is", "An", "Array"];

Object:

var javaScriptObject = { id: 0, thisIsAnArray: false };

And put it together:

var javaScriptArrayOfObjects = [ { id: 0, thisIsAnArray: false},{ id: 1, thisIsAnArray: false} ];

You can see that when you look at your JSON ( Java Script Object Notation ) you should be able to tell if it's an array of objects or an object with arrays.

this should point you to it being a complex object and not an array and David L's answer covers that perfectly.

I just wanted to touch on better understanding the error message.