Chapter review

For review, the complete version of the Default.aspx.cs file for this chapter, including comments, is shown in the following code block:

//using is a directive
//System is a name space
//name space is a collection of features that our needs to run
using System;//needed for EventArgs
using System.Collections.Generic;//needed for dictionary
using System.Diagnostics;//needed for Process.Start
//public means accessible anywhere
//partial means this class is split over multiple files
//class is a keyword and think of it as the outermost level of grouping
//:System.Web.UI.Page means our page inherits the features of a Page
public partial class _Default : System.Web.UI.Page
{
    protected void Button1_Click(object sender, EventArgs e)
    {
        //make a dictionary using string as the type for keys and values
        Dictionary<string, string> filePrograms = 
        new Dictionary<string, string>();
        //add two key/value pairs to the dictionary
        filePrograms.Add("notepad.exe", @"c:\data\samplefile.txt");
        filePrograms.Add("iexplore.exe", "http://www.bing.com");
        //iterate over the key/value pairs
        foreach(KeyValuePair<string, string> kvp in filePrograms)
        {
            //invoke Process.Start to launch notepad and internet explorer
            Process.Start(kvp.Key, kvp.Value);
        }
        //lines below get only at the key inside the filePrograms 
        //dictionary
        foreach(string key in filePrograms.Keys)
        {
            sampLabel.Text += $"<br>{key}";
        }
    }
}