How to convert datatable to json string using json.net?

Question

How to convert datatable to json using json.net? Any suggestion... I ve downloaded the necessary binaries... Which class should i use to get the conversion of my datatable to json? Thus far used this method to get json string by passing my datatable...

public string GetJSONString(DataTable table)
    {
        StringBuilder headStrBuilder = new StringBuilder(table.Columns.Count * 5); //pre-allocate some space, default is 16 bytes
        for (int i = 0; i < table.Columns.Count; i++)
        {
            headStrBuilder.AppendFormat("\"{0}\" : \"{0}{1}¾\",", table.Columns[i].Caption, i);
        }
        headStrBuilder.Remove(headStrBuilder.Length - 1, 1); // trim away last ,

        StringBuilder sb = new StringBuilder(table.Rows.Count * 5); //pre-allocate some space
        sb.Append("{\"");
        sb.Append(table.TableName);
        sb.Append("\" : [");
        for (int i = 0; i < table.Rows.Count; i++)
        {
            string tempStr = headStrBuilder.ToString();
            sb.Append("{");
            for (int j = 0; j < table.Columns.Count; j++)
            {
                table.Rows[i][j] = table.Rows[i][j].ToString().Replace("'", "");
                tempStr = tempStr.Replace(table.Columns[j] + j.ToString() + "¾", table.Rows[i][j].ToString());
            }
            sb.Append(tempStr + "},");
        }
        sb.Remove(sb.Length - 1, 1); // trim last ,
        sb.Append("]}");
        return sb.ToString();
    }

Now i thought of using json.net but dont know where to get started....

Answer 1

string json = JsonConvert.SerializeObject(table, Formatting.Indented);

编辑：当然，您不需要缩进格式，但它使它变得美观和可读。

Answer 2

Maybe it could help

Original version

public static class DataTableToJson
{
    public static JArray ToJson(this System.Data.DataTable source)
    {
        JArray result = new JArray();
        JObject row;
        foreach (System.Data.DataRow dr in source.Rows)
        {
            row = new JObject();
            foreach (System.Data.DataColumn col in source.Columns)
            {
                row.Add(col.ColumnName.Trim(), JToken.FromObject(dr[col]));
            }
            result.Add(row);
        }
        return result;
    }
}

Edited Version

There is a intermediate step because I needed to have a dictionary

public static IEnumerable<Dictionary<string, object>> ToDictionary(this DataTable table)
{
    string[] columns = table.Columns.Cast<DataColumn>().Select(c=>c.ColumnName).ToArray();
    IEnumerable<Dictionary<string, object>>  result = table.Rows.Cast<DataRow>()
            .Select(dr => columns.ToDictionary(c => c, c=> dr[c]));
    return result;
}

You can add JsonConverter.SerializeObject(result); , or another json serializer to get json string.

This is similar to @Hasan Javaid post

Answer 3

Check this.

private static string DataTableToJson(DataTable dataTable)
{
    JavaScriptSerializer serializer = new JavaScriptSerializer();
    var rows = (from DataRow d in dataTable.Rows
        select dataTable.Columns.Cast<DataColumn>().ToDictionary(col => col.ColumnName, col => d[col])).ToList();

    rows.AddRange(from DataRow d in dataTable.Rows
        select dataTable.Columns.Cast<DataColumn>().ToDictionary(col => col.ColumnName, col => d[col]));
    return serializer.Serialize(rows);
}