Melick's Blog

Recently I had a requirement to add Calculated Columns to Data Table. For an example I’m Only providing Amount and Quantity. Then discount will be calculated automatically. String Discount = ".1" ; DataTable workTable = new DataTable ( "Customers" ); DataColumn workCol = workTable.Columns.Add( "ID" , typeof ( Int32 )); workTable.Columns.Add( "UnitPrice" , typeof ( Double )); workTable.Columns.Add( "Quantity" , typeof ( Int16 )); workTable.Columns.Add( "Total" , typeof ( Double )); workTable.Columns.Add( "Discount" , typeof ( Double )); workTable.Columns[ "Total" ].Expression = "UnitPrice*Quantity" ; workTable.Columns[ "Discount" ].Expression = String .Format( "Total*{0}" ,Discount); Later you can bind the Data Table to a Grid View if you need. dataGridView1.DataSource = workTable; dataGridView1.Update(); Special Note: But my requirement was to update the Column Expression dynam...

This error occurred to me when I introduce ElevatedPrivilages block to the project. SPSecurity .RunWithElevatedPrivileges( delegate () {…} I refreshed the page and still I got the error. Then I found that I missed the web.AllowUnsafeUpdates = true ; in the code.

Eval() is a one way binding mechanism therefore it can be used as a ReadOnly expression. But Bind() works as a two way mechanism. therefore changes are getting reflect in the data source also.

I engaged with fining a method of dynamically change control’s background color in a ASP.NET grid based on data in the data source. I used the following code for get the task done. < asp : TemplateField HeaderText ="Color 01"> < ItemTemplate > < asp : Label ID ="lblColor1" runat ="server" BackColor =' <% # System.Drawing.ColorTranslator.FromHtml((String)Eval("Color1")) %> ' Text =' <% # Bind("Color1") %> ' > </ asp : Label > </ ItemTemplate > </ asp : TemplateField >