.NET-DataTable或DataSet转JSON

#region dataTable转换成Json格式  
/// <summary>  
/// dataTable转换成Json格式  
/// </summary>  
/// <param name="dt"></param>  
/// <returns></returns>  
public static string DataTable2Json(DataTable dt)  
{  
    StringBuilder jsonBuilder = new StringBuilder();  
    jsonBuilder.Append("{\"");  
    jsonBuilder.Append(dt.TableName.ToString());  
    jsonBuilder.Append("\":[");  
    for (int i = 0; i < dt.Rows.Count; i++)  
    {  
        jsonBuilder.Append("{");  
        for (int j = 0; j < dt.Columns.Count; j++)  
        {  
            jsonBuilder.Append("\"");  
            jsonBuilder.Append(dt.Columns[j].ColumnName);  
            jsonBuilder.Append("\":\"");  
            jsonBuilder.Append(dt.Rows[i][j].ToString());  
            jsonBuilder.Append("\",");  
        }  
        jsonBuilder.Remove(jsonBuilder.Length - 1, 1);  
        jsonBuilder.Append("},");  
    }  
    jsonBuilder.Remove(jsonBuilder.Length - 1, 1);  
    jsonBuilder.Append("]");  
    jsonBuilder.Append("}");  
    return jsonBuilder.ToString();  
}  
 
#endregion dataTable转换成Json格式  
 
#region DataSet转换成Json格式  
/// <summary>  
/// DataSet转换成Json格式  
/// </summary>  
/// <param name="ds">DataSet</param>  
/// <returns></returns>  
public static string Dataset2Json(DataSet ds)  
{  
    StringBuilder json = new StringBuilder();  
      
    foreach (DataTable dt in ds.Tables)  
    {  
        json.Append("{\"");  
        json.Append(dt.TableName);  
        json.Append("\":");  
        json.Append(DataTable2Json(dt));  
        json.Append("}");  
    }  
    return json.ToString();  
}  
#endregion