Stephens' C# Programming with Visual Studio® 2010 24-Hour Trainer

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LESSON 29 Reading and WRiting Files

2. Make a program that lets the user select a number from a NumericUpDown control and then

generates a file containing a multiplication table that goes up to that number times itself. Use

formatting to make the numbers line up in columns.

3. Build a program with a TextBox, a ListBox, an Add button, and a Save button. When the

user enters a value in the

TextBox and clicks Add, add the value to the ListBox. When the user

clicks Save, write the values from the

ListBox into a file and then clear the ListBox. When the

form loads, make it read the values back into the

ListBox.

4. Build a simple text editor. Give it a MenuStrip with Open and Save commands and a TextBox.

Use an

OpenFileDialog and a SaveFileDialog to let the user select the file to open and save.

(Don’t worry about any of the other things a real editor would need to handle, such as locked

files and ensuring that the user doesn’t close the program with unsaved changes.)

You can download the solutions to these exercises from the book’s web page at

www.wrox.com or www.CSharpHelper.com/24hour.html. You can find those

solutions in the Lesson29 folder.

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