Why should I use JSON with ASP.NET?

Question

Why should I use JSON with ASP.NET? Can you give a practical example? I have read articles but not so good.

Answer 1

How about when returning data from a Web Service ? Here are two methods that are suitable for .Net 2.0, that take a DataTable or a DataRow Parameter, and return a JSON formatted string to be sent over to the client, from the web service:

public string GetJson(DataRow r)
    {
        int index = 0;
        StringBuilder json = new StringBuilder();
        foreach (DataColumn item in r.Table.Columns)
        {
            json.Append(String.Format("\"{0}\" : \"{1}\"", item.ColumnName, r[item.ColumnName].ToString().Replace("\"","\\\"")));
            if (index < r.Table.Columns.Count - 1)
            {
                json.Append(", ");
            }
            index++;
        }
        return "{" + json.ToString() + "}";
    }

public string GetJson(DataTable t)
{
    int index = 0;
    StringBuilder json = new StringBuilder();
    foreach (DataRow currRow in t.Rows)
    {
        json.Append(GetJson(currRow));
        if (index < t.Rows.Count - 1)
        {
            json.Append(", ");
        }
    }
    return "[" + json.ToString() + "]";
}

The result can then be sent and evaluated on the Client.