Make a list box search

You need a listbox with items, a textbox and a button.

protected void Button1_Click(object sender, EventArgs e)

    {

        ListBoxPolicies.SelectedIndex = -1;

        for(int i=0; i< ListBox1.Items.Count; i++)

        {

            if (ListBox1.Items[i].ToString().Contains(TextBox1.Text))

            {

                ListBox1.SelectedIndex = i;

            }

        }

    }

Disable caching (Browser back button problem)

When the user hit the back button a locally cached copy of the previous page is retrieved without notifying the server. As a result the Info is out of sync.

Solution 1 --> Disable caching (do not work for all browsers)

Code to disable caching (to be executed everytime thepage is loaded)

Response.Cache.SetCacheability(HttpCacheability.NoCache);

Response.Cache.SetExpires(Now.AddSeconds(-1));   //--- (-1) means the page already expired

Response.Cache.SetNoStore();  //--tell the page not to cache the page

Response.AppendHeader("Pragma", "no-cache");  //---adds a header to the HTTP response object

Solution 2 --> Use timestamps or random numbers to track pages and detect when a page is current

Pad a string with zeros on the left/right in C# until completing n digits

Very simple way to pad with zeros until completing n digits

           

strMyString.PadLeft(n,'0');

Sample

string strMyString = "1234";

strMyString = strMyString.PadLeft(7,'0');

...will display "0001234"

Other notes: there is a .PadRight() function too.

Kill an Excel process in C#

foreach (System.Diagnostics.Process process in System.Diagnostics.Process.GetProcessesByName("EXCEL"))

        {

            if (process.MainModule.ModuleName.ToUpper().Equals("EXCEL.EXE"))

            {

                process.Kill();

                break;

            }

        }

Union of two dataTables and eliminate duplicates by using a customized IEqualityComparer

 public class StudentDataRowComparer : IEqualityComparer

    {

        #region IEqualityComparer Members

        public bool Equals(DataRow x, DataRow y)

        {

            return (x.Field("STUDENTID") == y.Field("STUDENTID"));

        }

        public int GetHashCode(DataRow obj)

        {

            return obj.ToString().GetHashCode();

        }

        #endregion

    }

 

How to call it

...

        //---Make an Union of both tables

        IEnumerable bothTables = dt1.AsEnumerable().Union(dt2.AsEnumerable());

                                DataTable dtUnion = bothTables.CopyToDataTable();

        //---Remove Duplicates

        var distinctStudents = dtUnion.AsEnumerable().Distinct( new StudentDataRowComparer());

                                DataTable dtFinal = distinctStudents.CopyToDataTable();

Sort a Listbox using IComparer in C#

What are we cooking today?

Sort a Listbox using IComparer in C# without loosing the value. 

RECIPE

The call

 SortList(MyListbox);

The Procedure

public void SortList(ListBox list)

{

        try

        {

            //---FROM LISTBOX TO LIST<>

            List ListItems = new List();

            foreach (ListItem lst in list.Items)

            {

                ListItems.Add(lst);

            }

            //---SORT LIST<>

            ListItemComparer listC = new ListItemComparer();

            ListItems.Sort(listC.Compare);

            //---CLEAR LISTBOX

            list.Items.Clear();

            //---ADD FROM ordered LIST<> to LISTBOX

            foreach (ListItem li in ListItems)

            {

                list.Items.Add(li);

            }

        }

        catch (Exception ex)

        {

            lblMsg.Text = ex.Message;

           

        }//--end catch

    }

The Icomparer: I am using this because a listitem has text and value, and we just want to order by the text, which could be a person's name or a product( the criteria could be also the value like price, personId, year...)

public class ListItemComparer : IComparer

{

    public int Compare(ListItem a, ListItem b)

    {

        int result = string.Compare(a.Text, b.Text);

        return result;

    }

}

Clear all the TextBoxes in a form

What are we cooking today?
How to clear TextBoxes in a form that uses masterpages. (C#)


Recipe

This procedure clears all the textboxes in a form. Please note this works when using a masterpage:
  
    public void ClearTextboxesInForm(string strContentPlaceHolder)
    {
        foreach (Control control in Form.Controls) 
        {
            if (control.ID == strContentPlaceHolder) 
            {
                foreach (Control ctrl in control.Controls)
                {
                    if (ctrl is TextBox)  //---Find the textboxes 
                    {
                        ((TextBox)ctrl).Text = "";
                    }
                }
            }
        }
    }