DataTableConverter
Converts a DataTable to and from JSON.
using Newtonsoft.Json.Serialization;
using Newtonsoft.Json.Utilities;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Globalization;
using System.Runtime.CompilerServices;
namespace Newtonsoft.Json.Converters
{
[System.Runtime.CompilerServices.NullableContext(1)]
[System.Runtime.CompilerServices.Nullable(0)]
public class DataTableConverter : JsonConverter
{
public override void WriteJson(JsonWriter writer, [System.Runtime.CompilerServices.Nullable(2)] object value, JsonSerializer serializer)
{
if (value == null)
writer.WriteNull();
else {
DataTable obj = (DataTable)value;
DefaultContractResolver defaultContractResolver = serializer.ContractResolver as DefaultContractResolver;
writer.WriteStartArray();
foreach (DataRow row in obj.Rows) {
writer.WriteStartObject();
foreach (DataColumn column in row.Table.Columns) {
object obj2 = row[column];
if (serializer.NullValueHandling != NullValueHandling.Ignore || (obj2 != null && obj2 != DBNull.Value)) {
writer.WritePropertyName((defaultContractResolver != null) ? defaultContractResolver.GetResolvedPropertyName(column.ColumnName) : column.ColumnName);
serializer.Serialize(writer, obj2);
}
}
writer.WriteEndObject();
}
writer.WriteEndArray();
}
}
[return: System.Runtime.CompilerServices.Nullable(2)]
public override object ReadJson(JsonReader reader, Type objectType, [System.Runtime.CompilerServices.Nullable(2)] object existingValue, JsonSerializer serializer)
{
if (reader.TokenType == JsonToken.Null)
return null;
DataTable dataTable = existingValue as DataTable;
if (dataTable == null)
dataTable = (((object)objectType == typeof(DataTable)) ? new DataTable() : ((DataTable)Activator.CreateInstance(objectType)));
if (reader.TokenType == JsonToken.PropertyName) {
dataTable.TableName = (string)reader.Value;
reader.ReadAndAssert();
if (reader.TokenType == JsonToken.Null)
return dataTable;
}
if (reader.TokenType != JsonToken.StartArray)
throw JsonSerializationException.Create(reader, "Unexpected JSON token when reading DataTable. Expected StartArray, got {0}.".FormatWith(CultureInfo.InvariantCulture, reader.TokenType));
reader.ReadAndAssert();
while (reader.TokenType != JsonToken.EndArray) {
CreateRow(reader, dataTable, serializer);
reader.ReadAndAssert();
}
return dataTable;
}
private static void CreateRow(JsonReader reader, DataTable dt, JsonSerializer serializer)
{
DataRow dataRow = dt.NewRow();
reader.ReadAndAssert();
while (reader.TokenType == JsonToken.PropertyName) {
string text = (string)reader.Value;
reader.ReadAndAssert();
DataColumn dataColumn = dt.Columns[text];
if (dataColumn == null) {
Type columnDataType = GetColumnDataType(reader);
dataColumn = new DataColumn(text, columnDataType);
dt.Columns.Add(dataColumn);
}
if ((object)dataColumn.DataType == typeof(DataTable)) {
if (reader.TokenType == JsonToken.StartArray)
reader.ReadAndAssert();
DataTable dataTable = new DataTable();
while (reader.TokenType != JsonToken.EndArray) {
CreateRow(reader, dataTable, serializer);
reader.ReadAndAssert();
}
dataRow[text] = dataTable;
} else if (!dataColumn.DataType.IsArray || (object)dataColumn.DataType == typeof(byte[])) {
object obj2 = dataRow[text] = ((reader.Value != null) ? (serializer.Deserialize(reader, dataColumn.DataType) ?? DBNull.Value) : DBNull.Value);
} else {
if (reader.TokenType == JsonToken.StartArray)
reader.ReadAndAssert();
List<object> list = new List<object>();
while (reader.TokenType != JsonToken.EndArray) {
list.Add(reader.Value);
reader.ReadAndAssert();
}
Array array = Array.CreateInstance(dataColumn.DataType.GetElementType(), list.Count);
((ICollection)list).CopyTo(array, 0);
dataRow[text] = array;
}
reader.ReadAndAssert();
}
dataRow.EndEdit();
dt.Rows.Add(dataRow);
}
private static Type GetColumnDataType(JsonReader reader)
{
JsonToken tokenType = reader.TokenType;
switch (tokenType) {
case JsonToken.Integer:
case JsonToken.Float:
case JsonToken.String:
case JsonToken.Boolean:
case JsonToken.Date:
case JsonToken.Bytes:
return reader.ValueType;
case JsonToken.Null:
case JsonToken.Undefined:
case JsonToken.EndArray:
return typeof(string);
case JsonToken.StartArray:
reader.ReadAndAssert();
if (reader.TokenType == JsonToken.StartObject)
return typeof(DataTable);
return GetColumnDataType(reader).MakeArrayType();
default:
throw JsonSerializationException.Create(reader, "Unexpected JSON token when reading DataTable: {0}".FormatWith(CultureInfo.InvariantCulture, tokenType));
}
}
public override bool CanConvert(Type valueType)
{
return typeof(DataTable).IsAssignableFrom(valueType);
}
}
}