Introduction to Help Text

•Online help to explain your program’s operation•“Splash screen”•Providing simple to understand prompts in dialog boxes•Handling errors in a graceful, helpful way•Adding help text to your Excel applications

Two Approaches to Online Help

•Method 1: Add a Help button, link to display a dialog box with help text, or use a MsgBox

•Method 2: “Official” help system provided by Windows

Help Method 1

Simple Stuff!

•Add “comments” to spreadsheet cells•Add a “text box”•Put extra information in one of the worksheets,•providing instructions, explanations - rename the•worksheet to “Help”.•UserForms with help text

Help Method 2: UserForms

•Create a UserForm•Add a Frame control•Insert a Label control•Set the Frame properties to allow scrolling•Write a section of initialization code to add the help text to the Label, and set the Label to fit the frame and allow scrolling (see HelpExamples.xls)

Help Method 2: Scrolling Label

•Label controls cannot contain a scroll bar•A frame control can contain a scroll bar•So we use a trick: We define a frame control with a scroll bar.•Then we enlarge the size of the Label to equal the size of the text added to it (AutoSize = True)•This makes the label bigger than the existing frame So we will tell the Frame to scroll through the height of the label

Help Method 3: WinHelp System

Most Windows applications use the Windows Help Systemor the newer HTML HelpSupports clickable links within help textSupports some text formattingRecommended: Use third-party help authoring products

Help Method 3: How It Works

You create a special “.hlp” help file that containshelp text items, each with a unique HelpContextID(e.g. 1001, 1002, 1003)On the properties list for a control, you enter the HelpContextID (and for form, “WhatsThis Button, True”When help is selected, Windows matches the HelpContextID(e.g. 1001) with the corresponding text in the .hlp fileand displays on screen.Details: Advanced topic!Also, in Office 2000, introducing HTML help

Help Summary

Method 1: Use comments, textboxes, “Help” sheet

Method 2: Create UserForms with your help text,link to a “Help” button

Method 3: Use Windows built-in help features

Week 14 - Topics•Last Time (refer to Week13.ppt)•Built-in functions commonly used in business applications

•String functions and formatting•Dates and Times•Formatting Data for output•Error handling

•Importing data from text, splitting text into columns•Importing data from text files: In-Class Exercise #1•Importing data using VBA: In-Class Exercise #2

Importing Data Into Excel

Models are built from dataData sources: market research reports, corporate data,Internet web sites, government research

•Entering data manually•Copying and pasting from IE (or other table)

•How to convert text into columnar data•Reading “delimited ASCII” text files•Writing VBA code to import data

Converting Text into Columns

Example: Paste some data from an external sourceSelect the range of cells that contains the pasted data.The range can be any number of rows tall, but no more than one column wide.

On the Data menu, click Text to Columns.Convert Text to Columns Wizard

Example

Select the first column only

Then choose Text to Columns… on the Data menu

Text to Columns Wizard

“Delimited” means that certain characters separate eachfield of data

Text to Columns Wizard Preview

Completed result

Importing Text Files

•You can also read text files directly into Excel.•Use Open on the File menu•At Files of type prompt, choose Text Files•This will launch the Text Import Wizard•(similar to the Text to Column Wizard)

•Some programs refer to this as “Delimited ASCII” files. Many spreadsheet, database and custom programs canexport their data in “Delimited ASCII” format, including Excel

Text Import Wizard

2 types of files: Delimited and Fixed Width

Text Import Wizard

Fixed-Width Data

"Under 5 years" 28,314 25,743 30,885"5 to 9 years" 29,606 25,471 33,741"10 to 14 years" 32,292 28,624 35,960"15 to 19 years" 29,854 25,300 34,408"20 to 24 years" 23,750 19,056 28,444"25 to 34 years" 53,725 49,419 58,032"35 to 44 years" 64,333 59,210 69,456"45 to 54 years" 57,700 53,900 61,500"55 to 59 years" 19,520 16,128 22,912"60 to 64 years" 13,618 10,481 16,755"65 to 74 years" 27,821 23,849 31,793"75 to 84 years" 18,323 15,092 21,554"85 years and over" 4,384 2,952 5,816

Fixed-Width Example

See FixedWidth.Txt example file

Reading & Writing Text Files

•You’ve seen how to import certain types of data•You can write VBA programs to read any kind of data file(since not all data files come set up just right for the TextFile Import Wizard, and may use non-standard delimiters)•You can write VBA programs to output data to files•VBA also includes functions to obtain file directories,rename or delete files, create directories and other tasks•We will focus on VBA’s text file read & write features.

Three Types of Files

VBA supports 3 types of data files:1. Sequential access (read or write from beginning to end)2. Random access (read or write at any location in file)3. Binary access (random access using internal binary data)

Types 2 and 3 not usually used in VBA so will focus on“sequential access” used for reading and writing text files

Working With Files

•Named files store data on disk•OPEN: Before you can read from - or write to - a file, you must first have your program “open” the file. This tells VBA what file you wish to use.•READ/WRITE: You use VBA statements to read (or get “input”) from the file, or write (“print”) data outputto the file.•CLOSE: When finished the file must be “closed”.

Opening a File To Read

(also known as “opening for input”)

Open “MyData.Txt” For Input As #1

Tells VBA to open the disk file “MyData.Txt”,that the file will be used for reading (input comesfrom the file)

Subsequently refer to the file as #1 in otherVBA statements. This associates the named filewith a file number or file channel for input/output.

Reading From the File

The easiest way to read an entire line of text fromthe opened file is to use the LINE INPUT # statement.Example:

Line Input #1, ReadDataString

This reads one line of data from the file and stores itin to the string variable ReadDataString. Once the datais in the string variable, you can use the string as youwould use any other string variable.

Detecting the End of FileWhen reading data from a file, your program willlikely eventually encountered the end of the file - in otherwords, there is no more data to read from the file.

This creates an Error condition that can be trapped withthe On Error Goto handler, or use the special EOF() function to test if the end of file has been reached.

While Not EOF(1)… Line Input #1, ReadDataString…

Loop

Example Data for File Demo

Elizabeth Morley/Spokane,WA 99205Bob Smith/Spokane,WA 99212Shamir Amed/Cheney,WA 99208Vladimir Ustov/Liberty_Lake,WA 99216

Note the non-standard data format using “/” sothe text import wizard cannot be used - will see how to process this in VBA

Example: ReadFileDemo1()

Sub ReadFileDemo1() Dim StartRow As Integer, Row_Of_Data As String StartRow = 1 Open "FileReadSampleData.txt" For Input As #1 Do While Not EOF(1) Line Input #1, Row_Of_Data Cells(StartRow, 1) = Row_Of_Data StartRow = StartRow + 1 Loop Close #1End Sub

Result of Running The Program

Processing the Input Data

Line Input #1, Row_Of_Data 'Expected data format: first lastname/city,state zip using string functions BlankPos = InStr(Row_Of_Data, " ") SlashPos = InStr(Row_Of_Data, "/") FirstName = Left(Row_Of_Data, BlankPos - 1) LastName = Mid(Row_Of_Data, BlankPos + 1, SlashPos - BlankPos - 1) CommaPos = InStr(Row_Of_Data, ",") CityName = Mid(Row_Of_Data, SlashPos + 1, CommaPos - SlashPos - 1) Comma2Pos = InStr(SlashPos, Row_Of_Data, ",") ' Start at position of / StateName = Mid(Row_Of_Data, Comma2Pos + 1, 2) ZipCode = Right(Row_Of_Data, 5)

Storing Data to The Worksheet

Cells(StartRow, 1) = FirstName Cells(StartRow, 2) = LastName Cells(StartRow, 3) = CityName Cells(StartRow, 4) = StateName Cells(StartRow, 5) = ZipCode

Example in ReadFileDemo2()

Writing Data To Files

To open a file to which text will be written, useOpen “filename” for Output as #1

Note: If the file already existed, this will overwrite ordestroy any previous data in the file. (See Append)

Then use either thePrint #1 statement

orWrite #1 statement

(Print and Write are slightly different)and Close #1 when all finished.

Writing Data To Files: Write #

Use Write # as in:Write #1, “The answer is “ & Result

If you use multiple variables, as,Write #1, “The answer is “, A, B, C

where A and B are numeric values and C is a Boolean, this writes“The Answer is”,2.18,16384,#TRUE#

where a comma character is inserted between each value(as for delimited text files)

Writing Data To Files: Print #

Print #1, “The answer is “ & ResultIf you use multiple variables, as in,

Print #1, “The answer is “, A, B, Cwhere A & B are numeric and C is a Boolean, this writes“The Answer is” 2.18 16384 #TRUE#where a TAB character is inserted between each value(as for delimited text files)

Sample Program

Output to files: See WriteFileDemo1()Reading the file: WriteFileDemo2()

Other Read statements: InputInput # is demonstrated in WriteFileDemo2()

Input #1, A, B, C, DAttempts to read each value from the file, separatedby commas, into the matching variables.

Very important that the variables match the data typesof the data in the file. Example of input data:

“some text”, 2.18, 100, #False#Input #1, StringVar, SingleVar, IntVar, BooleanVar

Line Input versus Input

Line Input reads an entire line or row of data from the inputfile, into a string variable. Used to read straight text or toread textual data that you will process with your own VBA code.

Input reads individual values, each separated by a comma,from the file. Easiest way to read individual data values intoyour program. The data format matches the format produced byWrite #. Makes it easy to write out data that is later read backinto a Visual Basic or VBA Excel application (as well as otherapplications)

Summary of File Reading

•Open “filename” for Input as #1 (or other file number)•Line Input #1, stringvariable to read a full line of text

or•Input #1, list of variables separated by commas•Close #1 when all finished•Use Eof(file number) to check for the end of file

Summary of File Writing

•Open “filename” for Output as #1 (or other file number)•Print #1, list of variables

or•Write #1, list of variables•Close #1 when all finished

Appending Data to a File

Open “filename” For Append As #1Print #1, A, B, CClose #1

“Append” opens the file for output, but new datais written starting at the end of the existing fileso that existing data is not overwritten.

Open for Output creates an entirely new file,deleting any old data.

Multiple Files Example

Open “file1.txt” for input as #1Open “file2.txt” for output As #2Do While Not Eof(1) Line Input #1, Line_Of_Text Print #2, Line_Of_TextLoopClose #2Close #1

What does this set of program statements do?

In Class Exercise #2Part 1:Following the example presented in lecture, create asubroutine named CreateFile that opens a file named “DataFile.txt” and writes the following items to the file:“This data file contains employment records”“Elizabeth Morley”,99205“Bob Smith”,99212“Shamar Amed”,99208“Vladimir Ustov”,99216

In-Class Exercise #2 (2)Part 2:Create a subroutine named ReadDataFile that opens the file named “DataFile.txt” for input and then readsthe first line (Line Input #1, FirstLine) of data and displays that in a message box.

Then, using the Do While Not Eof(1) statement,for each line of data, read the name into a

EmployeeName String variableand the Zipcode into a Single-type variable.Display using MsgBox EmployeeName & “ “

& ZipCode

Other File Operations

Error conditions: A properly written program shoulddetect if the Open statement fails because the file cannotbe found. You can do this with On Error Goto.

Other VBA functions (info in Excel/VBA Help)ChDir Kill (delete)CurDrive MkDirDir Name (rename)FileDataTime RmDir (delete directory)FileLen

Summary

At this point, you know more about using and applyingExcel to business problems than probably 98% to 99% ofall Excel users.•Solver business optimization models•Excel statistics and forecasting methods•Use of VBA to create custom applications