如何使用 Json.Net 将简单的 JSON 字符串解析为 DataSet

Question

我已经尝试了所有我能想到的尝试使用 JSON.net 库解析这个 JSON 字符串的方法，但我不断收到错误消息，提示“字符串反序列化后的附加文本”。有人对可能出现的问题有任何想法吗？

这是我拥有的 JSON 字符串：

{"w_vendor":["914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361","914115361"]}

这是我用来解析它的代码：

var pdfValue = Request["pdfValue"];
string OutputCacheLocation = JsonConvert.SerializeObject(pdfValue);
DataSet dataset = JsonConvert.DeserializeObject<DataSet>(pdfValue);

DataTable datatable = dataset.Tables["table1"];

Response.Write(datatable.Rows.Count);

有人看到错误所指的附加文本吗？我看不到它，而且 JSON 不会解析。我准备放弃并自己手动解析它。

Answer 1

您是否考虑过为您的数据创建一个自定义类并反序列化为，而不是反序列化为 DataSet？使用起来可能会更简单一些。

例如，如果你这样定义一个类：

class Data
{
    [JsonProperty(PropertyName="w_vendor")]
    public List<string> Values { get; set; }
}

然后你可以像这样反序列化：

string json = @"{""w_vendor"":[""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361"",""914115361""]}";

var data = JsonConvert.DeserializeObject<Data>(json);

Response.Write(data.Values.Count);

编辑

它没有按照您的方式工作的原因是因为您的数据不符合反序列化为DataSet 所需的结构。如果你看一下example from the documentation，数据的结构应该是这样的：

{
    "table1" : 
    [
        {
            "column1" : "value1",
            "column2" : "value2"
        },
        {
            "column1" : "value3",
            "column2" : "value4"
        }            
    ],
    "table2" : 
    [
        {
            "column1" : "value1",
            "column2" : "value2"
        },
        {
            "column1" : "value3",
            "column2" : "value4"
        }            
    ]
}

具体来说，外部对象包含表示表格的属性。属性名称对应于表的名称，值是 objects 的数组，其中每个对象代表表中的一行。对象的属性对应列名，其值为行数据。

在您的数据中，外部对象包含一个属性，其值是一个简单字符串数组，而不是对象。所以这不能变成表格，因为 JSON.NET 无法确定列名。此外，您的数据表的名称应该是 w_vendor，而不是 table1。