Excel-vba quick start (I. macros, VBA, procedures, types and variables, functions)

One 、Excel VBA Introduce

VBA（Visual Basic for Applications）, Is a way to extend Microsoft Office Functional programming language , Commonly used to extend Excel
function , by Excel Add automation scripts , And from improving Excel Office efficiency

1.1. macro

Macros are recording Excel The operation process , And then generate it automatically VBA Code tools , You can avoid writing a lot of VBA Code , It can be more simple
present Excel automation , But macros have limitations , When you want to implement functions with more complex logic , Still need to write VBA Code

1. Record macro

Microsoft Office Bring it with you VBA Related to the plug-in , But this article uses WPS Office, You need to install your own plug-ins to support VBA function ,
If you can't find the download address of the plug-in , You can leave a message

WPS Recording macros in is simple , Just follow the steps below ：

1. stay Excel Click on the development tool -> Record a new macro
2. From this moment on , Yes Excel Will be recorded , Click end recording when you want to stop

Attach a WPS Complete action diagram of macro recorded in , The recorded content is , by C1 Add cells =SUM(A1,B1) expression ：

2. other Excel Use recorded macros in the workbook

WPS Using macros in is just as simple , Just follow the steps below ：

1. Open... With macro Excel workbook
2. Open the workbook where you want to use macros
3. Click... In the workbook where you want to use the macro development tool -> VB macro -> Select the macro to use by name -> Can run

Attach a WPS The complete operation diagram of the macro used in , The contents of the macro are , by C1 Add cells =SUM(A1,B1) expression ：

3. View the automatically generated... After recording a macro VBA Code

WPS View the corresponding... In the macro VBA Code , Just follow the steps below ：

1. Open... With macro Excel workbook
2. Click... In the workbook where you want to use the macro development tool -> VB macro -> Select the macro to use by name -> edit

Attach a WPS View the macro automatically generated VBA Dynamic diagram of code ：

Although the example is simple , But it can also show the basic functions of macros

1.2. Visual Basic Editor

Whether it's Microsoft Office still WPS Office,VBA The code is generic , Generally used to Visual Basic Editor to write VBA generation
code , stay WPS Open in Visual Basic The editor works as follows

Visual Basic Introduction to the basic layout of the editor

Because I didn't want to VBA Study too deeply , So for VB Editor interface , Simply understand the following important places

1. Where the code is written

2. Common windows

3. Other common windows

Two 、VBA - Define the process

grammar

adopt Sub Keyword to define the process , Multiple processes can be defined in a module , Each process is actually a macro , Can be used alone ,
It can also be passed in one process Call The process of To call another procedure ：

Sub  Process name ()
  ' Process content 
End Sub

demonstration

stay Excel Use in VBA There are generally two ways to code , One is triggered by events , One is triggered by a form control , Now through the form control
To demonstrate how to use VBA Code

1. The following processes are defined in the module ：

Sub studyVBA()
  Sheet1.Cells(1, 1) = " Start today VBA!!"
End Sub

2. stay Excel Add a button to the worksheet , And specify a macro for it （ We define the process name ）：

3、 ... and 、VBA - Types and variables

1. data type

To define a variable, you must first know what type of variable you want to define ,VBA There are many data types in , Commonly used ：

Type the name	keyword	Keyword abbreviation
integer	Integer	%
Long integer	Long	&
Single precision	Single	!
Double precision	Double	#
Character	String	$

It is not recommended to use abbreviations when declaring types ,VBA In addition to the basic types , Object types are also supported

2. Defining variables

stay VBA A common way to declare variables in is Public and Dim,Dim The declared variable is a local temporary variable , Its scope is its structure ,
Public Declared variables are generally defined in the global , Not defined in a process

When learning related knowledge later , Can also learn Public Other USES , And other ways of defining variables

Declare variable syntax ：

Dim  Variable name  As  data type 
Public  Variable name  As  data type 

Declare variables to demonstrate ：

Public globalNum As Integer

Sub studyVBA()
  Dim localNum As Integer
End Sub

Variable assignment ：

Simply declaring variables is not enough , We also need to assign values to variables , There are two ways to assign values to variables ：

1. Assign values to variables of basic types , Use it directly Variable name = value The grammar of
2. Assign values to variables of object type , Need to make use of Set keyword , The grammar is Set Variable name = value

Demonstration of variable assignment ：

Sub studyVBA()
  '  Assign values to variables of basic types 
  Dim localNum As Integer
  localNum = 100
  
  '  Assign values to object type variables  
  Dim obj As Range
  Set obj = Range("a1")
End Sub

Four 、VBA - function

1. Ordinary function

Define the syntax for ordinary functions ：

Function  The name of the function ( Parameters 1, Parameters 2,  Parameters n)
   Logic code 
   The name of the function = Return value 
End Function

Examples of defining common functions ：

' Defined function 
Function setValue(num1, num2)
  setValue = num1 + num2
End Function

Examples of calling normal functions ：

1. Use the defined function in the procedure

' Call a function in a procedure 
Sub invoke()
  Sheet1.Cells(1, 1) = setValue(1, 2)
End Sub

2. stay Excel The defined function is used as a function expression in

2. Function with optional arguments

Function with optional arguments ： When defining a function , Specify that the parameter is optional , This parameter can be passed when calling the function , Don't pass it on

Functions that define optional parameters - grammar ：

Function  The name of the function ( Parameters 1,Optional  Parameters 2 as  type , Parameters n)
   Logic code 
   The name of the function = Return value 
End Function

Functions that define optional parameters - Example ：

' Defined function 
Function setValue(num1, Optional num2 As Integer)
  setValue = num1 + num2
End Function

Call a function with optional arguments - Example ：

It is no different from calling ordinary functions , Only the parameters can be selected

' Call a function in a procedure , Choose not to pass in the second parameter 
Sub invoke()
  Sheet1.Cells(1, 1) = setValue(5)
End Sub

3. Functions with default values for arguments

Functions with default values for arguments ： On the basis of functions with optional parameters , Set the default value for parameters without value transfer

Define functions with default values for parameters - grammar ：

Function  The name of the function ( Parameters 1,Optional  Parameters 2 as  type  =  The default value is , Parameters n)
   Logic code 
   The name of the function = Return value 
End Function

Define functions with default values for parameters - Example ：

' Defined function 
Function setValue(num1, Optional num2 As Integer = 100)
  setValue = num1 + num2
End Function

Call a function with a default value for the parameter - Example ：

' Call a function in a procedure , Choose not to pass in the second parameter 
Sub invoke()
  Sheet1.Cells(1, 1) = setValue(5)
End Sub

4. When calling a function, specify the parameter name to pass the value

When a function is called , If you do not want to pass in parameter values in the order of the parameter list , You can also use Function name ( Parameter name := Parameter values ) This kind of lattice for specifying parameter names
To make a function call

Example

Sub invoke()
  Sheet1.Cells(1, 1) = setValue(num2:=100, num1:=200)
End Sub

5. Functions with variable length argument lists

When defining a function , The number of parameters cannot be determined , It needs to be decided by the caller when the function is called , In this scenario, functions with variable length parameter lists can be used

Functions with variable length argument lists - grammar

The function of variable length parameter list is to change the passed parameters into an array

Function  Function name (ParamArray  Parameter name ())
End Function

Example

Functions that define variable length parameter lists

' Defined function 
Function setValue(ParamArray params())
  For Each Item In params
    Debug.Print Item
  Next
End Function

Call the function of variable length parameter list

' Call function 
Sub invoke()
  ' The parameter list does not need parentheses when the return value is not required 
  setValue 5, 6
  ' The parameter list must have parentheses when a return value is required 
  Dim returnVal As Integer
  returnVal = setValue(5, 6)
End Sub

Function definition in either way , If you want to use the return value of the function when calling , The parameter list must be written in parentheses when calling , If not
Use the return value , Parentheses can be omitted from the call