Computer Programming Concepts and Visual Basic David I. Schneider

EXAMPLE 4
In the following solution to Example 1, the file name is provided by the user in an input box.
Private Sub cmdDisplay_Click()
Dim fileName As String, prompt As String, title As String
Dim houseNumber As Single, street As String
picAddress.Cls
prompt = “Enter the name of the file containing the information.”
title = “Name of File”
fileName = InputBox(prompt, title)
Open fileName For Input As #1
Input #1, houseNumber
Input #1, street
picAddress.Print “The White House is located at”; houseNumber; street
Close #1
End Sub
[Run, and then click the command button. The input box of Figure 2-25 appears on the screen. Type
DATA.TXT (possibly preceded with a path) into the input box and click on OK. The input box disappears
and the following appears in the picture box.]
The White House is located at 1600 Pennsylvania Ave.
The response typed into an input box is treated as a single string value, no matter what
is typed. (Quotation marks are not needed and, if included, are considered as part of the
string.) Numeric data typed into an input box should be converted to a number with Val
before it is assigned to a numeric variable or used in a calculation.
■ FORMATTING OUTPUT WITH PRINT ZONES
Each line in a picture box can be thought of as being subdivided into zones, as shown in Figure
2-27. Each zone contains 14 positions, where the width of a position is the average width of
the characters in the font.
FIGURE 2-27 Print Zones
We have seen that when the Print method is followed by several items separated by semicolons,
the items are displayed one after another. When commas are used instead of semicolons,
the items are displayed in consecutive zones. For instance, if the Font property of
picBox is set to Courier, when the motto of the state of Alaska is displayed with the statements
picBox.Print “North”, “to”, “the”, “future.”
picBox.Print “12345678901234567890123456789012345678901234567890”
the resulting picture box is
where each word is in a separate print zone. This same output can be achieved with the code
Input and Output 53