8/15/2019 VBA in Arcgis-Muhanad(1)

1/24

VBA IN ARCGISBy: Muhanad Gaafar Osman

8/15/2019 VBA in Arcgis-Muhanad(1)

2/24

What is Visual Basic?

• Is a tool that allows you to develop Windows (Graphic serInterface ! GI" applications# $he applications have a familappearance to the user#

• Is event!driven% meanin& code remains idle until called uporespond to some event ('utton pressin&% menu selection% ##

•

 is &overned 'y an event processor# othin& happens until event is detected# Once an event is detected% the codecorrespondin& to that event (event procedure" is e)ecuted#

8/15/2019 VBA in Arcgis-Muhanad(1)

3/24

*ome +eatures of Visual Basic

• +ull set of o',ects ! you -draw- the application

• .ots of icons and pictures for your use#

• /esponse to mouse and 0ey'oard actions1

• 2lip'oard and printer access#

• +ull array of mathematical% strin& handlin&% and &raphics functions#

• 2an handle 3)ed and dynamic varia'le and control arrays#

• *e4uential and random access 3le support#

• seful de'u&&er and error!handlin& facilities#

• 5owerful data'ase access tools#

• 6ctive7 support#

• 5ac0a&e 8 9eployment Wiard ma0es distri'utin& your applications simple

8/15/2019 VBA in Arcgis-Muhanad(1)

4/24

*tructure of a Visual Basic6pplicationApplication (Project) is made up of:

• Forms ! Windows that you create for user interface#

• Controls ! Graphical features drawn on forms to allow user interaction (te)t 'o)es% l'ars% command 'uttons% etc#" (+orms and 2ontrols are o',ects#"#

• Properties ! ;very characteristic of a form or control is speci3ed 'y a property# ;)aproperties include names% captions% sie% color% position% and contents# Visual Basic adefault properties#

8/15/2019 VBA in Arcgis-Muhanad(1)

5/24

*teps in 9evelopin& 6pplicatio

$!ere are t!ree primar% stepsin#ol#ed in &uildin' a Visual Basiapplication:

=# 9raw the user interface#># 6ssi&n properties to controls#

# 6ttach code to controls

8/15/2019 VBA in Arcgis-Muhanad(1)

6/24

Varia'les

• Varia'les are used 'y Visual Basic to hold information needyour application# /ules used in namin& varia'les:

• @ o more than A characters

• @ $hey may include letters% num'ers% and underscore (C"

• @ $he 3rst character must 'e a letter

• @

8/15/2019 VBA in Arcgis-Muhanad(1)

7/24

Visual Basic 9ata $ypes:

• Boolean

• Inte&er

• .on& (Inte&er"

• *in&le (+loatin&"

• 9ou'le (+loatin&"

• 2urrency• 9ate

• O',ect

• *trin&

• Variant

8/15/2019 VBA in Arcgis-Muhanad(1)

8/24

• varia'les are declared usin& the istatement:

•im MyInt as Inte&er•im My9ou'le as 9ou'le

•im My*trin&%

8/15/2019 VBA in Arcgis-Muhanad(1)

9/24

Visual Basic *tatements and;)pressions $he simplest statement is the assi&nment statement# Iconsists of a varia'le name% followed 'y the assi&nmenoperator (D"% followed 'y some sort of e)pression#

•"amples:• *tart$ime D ow

• ;)plorer#2aption D E2aptain *pauldin&E• Bit2ount D Byte2ount F

• ;ner&y D Mass F .IGH$*5;;9 >

• etWorth D 6ssets ! .ia'ilities

 $he assi&nment statement stores information#

8/15/2019 VBA in Arcgis-Muhanad(1)

10/24

Visual Basic Operators $he simplest operators carry out arithmetic operations# $hese operaorder of precedence are:

*perator *peration

;)ponentiation

FJ Multiplication and division

K Inte&er division (truncates"

Mod Modulus

L ! 6ddition and su'utraction

 $o concatentate two strin&s% use the 8 sym'ol or the L sym'ol:

l'l$ime#2aption D E$he current time isE 8 +ormat(ow% hh:mmN"

t)t*ample#$e)t D EHoo0 this L to thisN

8/15/2019 VBA in Arcgis-Muhanad(1)

11/24

comparison operators $here are si) comparison operators in Visual Basic:

*perator Comparison

Greater than

P .ess than

D Greater than or e4ual

PD .ess than or e4ual to

D ;4ual to

P ot e4ual to

The result of a comparison operation is a Boolean value (True or Fa

8/15/2019 VBA in Arcgis-Muhanad(1)

12/24

.o&ical OperatorsWe will use three lo&ical operators

*perator *perationot .o&ical not

6nd .o&ical and

Or .o&ical or

• $he ot operator simply ne&ates an operand#• $he 6nd operator returns a $rue if 'oth operands are $rue# ;lse% it ret

• $he Or operator returns a $rue if either of its operands is $rue% else it +alse#

•  .o&ical operators follow arithmetic operators in precedence#

8/15/2019 VBA in Arcgis-Muhanad(1)

13/24

If *tatements

• $he simplest is the IfJ$hen statement:

If  Balance ! 2hec0 P  $hen 5rintE

8/15/2019 VBA in Arcgis-Muhanad(1)

14/24

• 

8/15/2019 VBA in Arcgis-Muhanad(1)

15/24

• Or% we can add the ;lseIf statement:

If  Balance ! 2hec0 P  $hen

5rint E

8/15/2019 VBA in Arcgis-Muhanad(1)

16/24

Visual Basic .oopin&

• .oopin& is done with the o+,oop format# .oops are used operations are to 'e repeated some num'er of times# $he repeats until some speci3ed condition at the 'e&innin& or ethe loop is met#

• 9o WhileJ.oop ;)ample:

2ounter D =

9o While 2ounter PD =

9e'urint 2ounter

2ounter D 2ounter L =

.oop

8/15/2019 VBA in Arcgis-Muhanad(1)

17/24

•9o ntilJ.oop ;)ample:

2ounter D =9o ntil 2ounter =

9e'urint 2ounter2ounter D 2ounter L =.oop

8/15/2019 VBA in Arcgis-Muhanad(1)

18/24

•9oJ.oop While ;)ample:

*um D =9o

9e'urint *um*um D *um L

.oop While *um PD R

8/15/2019 VBA in Arcgis-Muhanad(1)

19/24

•9oJ.oop ntil ;)ample:

*um D =9o

9e'urint *um*um D *um L .oop ntil *um R

8/15/2019 VBA in Arcgis-Muhanad(1)

20/24

+orJe)t loop

2ountin& is accomplished usin& the +orJe)t loop#

;)ample

+or I D = to R *tep >

6 D I F >

9e'urint 6

e)t I

8/15/2019 VBA in Arcgis-Muhanad(1)

21/24

Pro'rammin' -it! *&jects:

•6rcO',ects is a set of pro&ramma'leo',ects

•Visual Basic 6pplication (VB6" is ano',ect Soriented pro&rammin& lan&uSoriented pro&rammin& lan&ua&e

•VB6 is included with 6rcGI* 9es0top(6rcMap and 6rc2atalo&"1

8/15/2019 VBA in Arcgis-Muhanad(1)

22/24

*tartin& the Visual Basi;ditor:

8/15/2019 VBA in Arcgis-Muhanad(1)

23/24

;)plorin& the VB6 *ections:

8/15/2019 VBA in Arcgis-Muhanad(1)

24/24

6rcO',ectT