Just keep going with your code – you’re on the right track: //call SQL helper class to get initial data DataTable dt = sql.ExecuteDataTable(“sp_MyProc”); dt.Columns.Add(“NewColumn”, typeof(System.Int32)); foreach(DataRow row in dt.Rows) { //need to set value to NewColumn column row[“NewColumn”] = 0; // or set it to some other value } // possibly save your Dataset … Read more
You can use DataView. DataView dv = new DataView(yourDatatable); dv.RowFilter = “query”; // query example = “id = 10” http://www.csharp-examples.net/dataview-rowfilter/
With a break point set, after the DataTable or DataSet is populated, you can see a magnifying glass if you hover over the variable. If you click on it, it will bring up the DataTable Visualizer, which you can read about here. In this image you see below, dt is my DataTable variable and the … Read more
If you need a weak reference to the cell value: object field = d.Rows[0][3] or object field = d.Rows[0].ItemArray[3] Should do it If you need a strongly typed reference (string in your case) you can use the DataRowExtensions.Field extension method: string field = d.Rows[0].Field<string>(3); (make sure System.Data is in listed in the namespaces in this … Read more
This code snippet from Convert Datatable to JSON String in C#, VB.NET might help you. It uses System.Web.Script.Serialization.JavaScriptSerializer to serialize the contents to JSON format: public string ConvertDataTabletoString() { DataTable dt = new DataTable(); using (SqlConnection con = new SqlConnection(“Data Source=SureshDasari;Initial Catalog=master;Integrated Security=true”)) { using (SqlCommand cmd = new SqlCommand(“select title=City,lat=latitude,lng=longitude,description from LocationDetails”, con)) { … Read more
Try comparing the value of the column to the DBNull.Value value to filter and manage null values in whatever way you see fit. foreach(DataRow row in table.Rows) { object value = row[“ColumnName”]; if (value == DBNull.Value) // do something else // do something else } More information about the DBNull class If you want to … Read more
As to the cause, the <f:attribute> is specific to the component itself (populated during view build time), not to the iterated row (populated during view render time). There are several ways to achieve the requirement. If your servletcontainer supports a minimum of Servlet 3.0 / EL 2.2, then just pass it as an argument of … Read more
You can use LINQ-to-DataSet with Enumerable.Any: String author = “John Grisham”; bool contains = tbl.AsEnumerable().Any(row => author == row.Field<String>(“Author”)); Another approach is to use DataTable.Select: DataRow[] foundAuthors = tbl.Select(“Author=”” + searchAuthor + “””); if(foundAuthors.Length != 0) { // do something… } Q: what if we do not know the columns Headers and we want to … Read more
Try to use the DataColumn.SetOrdinal method. For example: dataTable.Columns[“Qty”].SetOrdinal(0); dataTable.Columns[“Unit”].SetOrdinal(1); UPDATE: This answer received much more attention than I expected. To avoid confusion and make it easier to use I decided to create an extension method for column ordering in DataTable: Extension method: public static class DataTableExtensions { public static void SetColumnsOrder(this DataTable table, params … Read more
You can simply check like this: return row.Table.Columns.Contains(columnName);