Asp.net C# 把 Datatable转换成JSON 字符串

First of all, we have to fetch the records from the database (MS Sqlserver) into the C# DataTable, or we can add dynamic rows to our DataTable. So our code looks like as written below.

//*

public DataTable getData()

{

DataTable dt = new DataTable();

dt.Columns.Add("UserId", typeof(Int32));

dt.Columns.Add("UserName", typeof(string));

dt.Columns.Add("Education", typeof(string));

dt.Columns.Add("Location", typeof(string));

dt.Rows.Add(1, "Satinder Singh", "Bsc Com Sci", "Mumbai");

dt.Rows.Add(2, "Amit Sarna", "Mstr Com Sci", "Mumbai");

dt.Rows.Add(3, "Andrea Ely", "Bsc Bio-Chemistry", "Queensland");

dt.Rows.Add(4, "Leslie Mac", "MSC", "Town-ville");

dt.Rows.Add(5, "Vaibhav Adhyapak", "MBA", "New Delhi");

dt.Rows.Add(6, "Johny Dave", "MCA", "Texas");

return dt;

}

 

方法一：Fetch each data (value), and append to our jsonString StringBuilder. This is how our code looks like

 

public string DataTableToJsonWithStringBuilder(DataTable table)

{

   var jsonString = new StringBuilder();

   if (table.Rows.Count > 0)

   {

   jsonString.Append("[");

   for (int i = 0; i < table.Rows.Count; i++)

   {

   jsonString.Append("{");

   for (int j = 0; j < table.Columns.Count; j++)

   {

   if (j < table.Columns.Count - 1)

   {

   jsonString.Append("\"" + table.Columns[j].ColumnName.ToString()

+ "\":" + "\""

+ table.Rows[i][j].ToString() + "\",");

   }

   else if (j == table.Columns.Count - 1)

   {

   jsonString.Append("\"" + table.Columns[j].ColumnName.ToString()

+ "\":" + "\""

+ table.Rows[i][j].ToString() + "\"");

   }

   }

   if (i == table.Rows.Count - 1)

   {

   jsonString.Append("}");

   }

   else

   {

   jsonString.Append("},");

   }

   }

   jsonString.Append("]");

   }

return jsonString.ToString();

}

//*

 

方法 2: Convert DataTable to JSON using JavaScriptSerializer:

public string DataTableToJsonWithJavaScriptSerializer(DataTable table)

{

JavaScriptSerializer jsSerializer = new JavaScriptSerializer();

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

Dictionary<string, object> childRow;

foreach (DataRow row in table.Rows)

{

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

foreach (DataColumn col in table.Columns)

{

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

}

parentRow.Add(childRow);

}

return jsSerializer.Serialize(parentRow);

}

 

方法3（推荐）: Convert DataTable to JSON using Json.Net DLL (Newtonsoft):

public string DataTableToJsonWithJsonNet(DataTable table)

{

   string jsonString=string.Empty;

   jsonString = JsonConvert.SerializeObject(table);

   return jsonString;

}