출처 : 본인

출처2 : https://msdn.microsoft.com/ko-kr/library/system.web.script.serialization.javascriptserializer(v=vs.90).aspx

출처3 : http://stackoverflow.com/questions/6535492/c-sharp-3-5-partial-class-string-isnullorwhitespace

우선 참조에 System.Web.Extensions 를 추가한다.

확장메서드로 구현하였기 때문에

DataTable.ToJson();

과 같은 식으로 사용하면 된다.

또는

CommonExtensions.ToJson(DataTable);

과 같이 사용해도 된다.

using System.Collections.Generic;

using System.Data;

public static class CommonExtensions

{

public static string ToJson(this DataTable value)

{

System.Web.Script.Serialization.JavaScriptSerializer serializer = new System.Web.Script.Serialization.JavaScriptSerializer();

serializer.MaxJsonLength = 2147483647;

List<Dictionary<string, object>> rows = new List<Dictionary<string, object>>();

Dictionary<string, object> row;

foreach (DataRow dr in value.Rows)

{

row = new Dictionary<string, object>();

foreach (DataColumn col in value.Columns)

{

row.Add(col.ColumnName, dr[col]);

}

rows.Add(row);

}

return serializer.Serialize(rows);

}

public static string ToJson(this DataSet value)

{

System.Web.Script.Serialization.JavaScriptSerializer serializer = new System.Web.Script.Serialization.JavaScriptSerializer();

serializer.MaxJsonLength = 2147483647;

Dictionary<string, List<Dictionary<string, object>>> dsList = new Dictionary<string, List<Dictionary<string, object>>>();

List<Dictionary<string, object>> rows;

Dictionary<string, object> row;

foreach (DataTable dt in value.Tables)

{

rows = new List<Dictionary<string, object>>();

foreach (DataRow dr in dt.Rows)

{

row = new Dictionary<string, object>();

foreach (DataColumn col in dt.Columns)

{

row.Add(col.ColumnName, dr[col]);

}

rows.Add(row);

}

dsList.Add(dt.TableName, rows);

}

return serializer.Serialize(dsList);

}

}

데이터테이블을 Json으로 변환 DataTable to Json string