how do i pass variables between two button click events

One way to resolve your problem would be to create a small class for your data and add instances of it to the ListBox.

Something like:

public class SearchItem
{
  public string LastName {get; set;}
  public int ID {get; set;}

  public override string ToString()
  {
      return this.LastName;
  }
  ..........
  ..........
  ..........
}

Then to use this:

SearchItem newItem = null;
while (reader.Read())
{
  newItem = new SearchItem();
  newItem.LastName = reader["Lname"].ToString();
  newItem.ID = reader["ID"].ToString();
  searchresults.Items.Add(newItem);
}

To access the Id:

int testID = ((SearchItem)searchresults.Items[x]).ID;

Hope this helps. :)

Create a class for your search results with properties of the query results.

public class Applicant
{
public int ID { get; set; }
public string LName { get; set; }
//the rest of parameters
}

while reading, create new instances of Applicant, fill the parameters and insert these instances to the Listbox:

....
Applicant newApplicant;
using (SqlConnection conn)
{
...
using(SqlDatareader reader = cmd.ExecuteReader())
{
while (reader.Read())
    {
        newApplicant = new Applicant();
        newApplicant.ID = reader.GetInt32(0);
        newApplicant.LName = reader.GetString(1);
        ....
        ListBox.Items.Add(newApplicant);
    }
}
}

By this way, in the listbox you will have instances of Applicant. Under button b, you can get the selected id as:

Applicant selectedApplicant = ListBox1.SelectedItem as Applicant;
int requiredID = selectedApplicant.ID;

As two quick notes, I highly recommend using SqlParameter in sql queries instead of string addition and close any reasources after you are done (like connections, readers, etc)

its very simple to pass value in c#..
U have to assign a value to the session variable in which u need to pass it..
syntax:

session["variable_name"]= passing_value;

then u have to retrieve the value from another button event..
lik..

local_variable= session["variable_name"].tostring();

try this one it will help u..

best of luck..

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