Что такое string vba excel

The string is a data type that holds a sequence of characters like the alphabet, special characters, and numbers. In VBA we can manipulate strings in such a way, that we can do concatenation, we can also reverse a string, and also add or remove any string in a string. In this article, we will learn about excel VBA strings. 

Declaration of String

Strings are a combination of characters. Strings can be declared in the same way as integers or characters are declared in VBA. For example, Dim str As String, here str is a variable with the string data type. 

Assigning String value

String value should be surrounded with double quotes whenever it will be assigned to a string variable. For example, str = “I am Ayush”, here “I am Ayush”, is assigned in the double quotes. 

Concatenation

Concatenation means the joining of two strings, into one string, using the “&” operator. For example, str = “Ayu”, str1 = “sh”, can be concatenated/joined into one string, str2 by str & str1. The final output of str2 is “Ayush”. 

String Manipulation

String manipulation is a concept that provides us with different in-built functions which help to manipulate the string. There are fifteen-plus functions in string manipulation, but here we will discuss some of the most commonly used string manipulation functions. For example, like LCase, UCase, Replace, and StrReverse. 

LCase()

The LCase() function, returns the string after converting it into lowercase. The function takes one mandatory argument i.e. input_string. 

Syntax of the function: LCase(input_string)

For example, “AYUSH” string has to be converted, into a lowercase string. Use LCase(“AYUSH”), and update the returned value of the function, with the original string i.e. str. The final output will be “ayush”. 

UCase()

The UCase() function, returns the string after converting it into uppercase. The function takes one mandatory argument i.e. input_string.

Syntax of the function: UCase(input_string)

For example, “ayush” string has to be converted, into an uppercase string. Use UCase(“ayush”), and update the returned value of the function, with the original string i.e. str. The final output will be “ayush”. 

Replace()

The Replace() function, replaces a part of the string with another string. The function takes three mandatory arguments i.e. input_string, string2, string3.

Syntax of the function: Replace(input_string, string2, string3)

input_string: It is the first argument of the replace() function. It takes the required string on which you want to apply the replacement. 

string2: It is the second argument of the replace() function. It is the string, which will be replaced in input_string. This string should be a sub-string of input_string. 

string3: It is the third argument of the replace() function. It is the new string, which will be replaced in place of string2. 

For example, consider a string “Codimh”, the “mh” substring can be replaced with “ng”, in the given input string. Use, Replace(“Codimh”, “mh”, “ng”), function, to replace old string with the new string. The final output of str is Coding.  

StrReverse()

The StrReverse() function, returns the reverse of a string. The function takes one mandatory argument i.e. input_string.

Syntax of the function: StrReverse(input_string)

For example, consider a string “Coding”, the given string can be reversed using StrReverse(“Coding”). The returned value of the given function is updated to the string str. The final output of the str is “gnidoC”. 

Substring Functions

There are 3 different types of substring functions, these functions return a substring in a string. 

Left()

The Left() function, returns the substring from the left side of the string. The function takes two mandatory arguments i.e. input_string and number. 

Syntax of the function: Left(input_string, number)

input_string: It is the first argument of the Left() function. It is the input string, for which the left substring has to be returned. 

number: It is the second argument of the Left() function. It tells the number of characters to be returned from the left start of the string. 

For example, consider a string “Coding”, a left substring of length two can be returned using Left(“Coding”, 2). The final output of the str is “Co”.

Right()

The Right() function, returns the substring from the right side of the string. The function takes two mandatory arguments i.e. input_string and number.

Syntax of the function: Right(input_string, number)

input_string: It is the first argument of the Right() function. It is the input string, for which the right substring has to be returned. 

number: It is the second argument of the Right() function. It tells the number of characters to be returned from the right start of the string. 

For example, consider a string “Coding”, a right substring of length two can be returned using Right(“Coding”, 2). The final output of the str is “ng”.

Mid()

The Mid() function, returns a substring of any size a user wants. The function takes three mandatory arguments i.e. input_string, number1, and number2.

Syntax of the function: Mid(input_string, number1, number2)

input_string: It is the first argument of the Mid() function. It is the input string, for which the substring has to be returned. 

number1: It is the second argument of the Mid() function. It tells the starting index of the substring. 

number2: It is the third argument of the Mid() function. It tells the number of characters of the substring. 

For example, consider a string “Coding”, and we need to return a substring “odi”. This can be achieved using the Mid(“Coding”, 2, 3) function. 

Note: 1-based indexing of string has been considered in the Mid() function. 

Length and Position

Len() 

The Len() function, returns the length of the string. The function takes one mandatory argument i.e. input_string. 

Syntax of the function: Len(input_string)

input_string: It is the first argument of the Len() function. It is the input string, for which the length has to be returned.

For example, consider a string “Coding”, the length of the string can be achieved by using Len(“Coding”). The final output of the program is 6. 

InStr()

The InStr() function, returns the first position of a substring in the string. The function takes three mandatory arguments i.e. number1, input_string, and string. 

Syntax of the function: InStr(number1, input_string, string)

number1: It is the first argument of the InStr() function. This number tells the position of the start of the search in the input_string. 

input_string: It is the second argument of the InStr() function. It is the input string, in which the search has to be made. 

string: It is the third argument of the InStr() function. It is the string that has to be searched in the input_string. 

For example, consider a string “Coding”, the start of the search is from index 1 i.e. character ‘C’, and the substring to be searched is “o”. This could be achieved using InStr(1, “Coding”, “o”). The final output of the program is 2. 

String Variable Type

The String data type is one of the most common data types in VBA. It stores “strings” of text.

To declare an variable String variable, you use the Dim Statement (short for Dimension):

Dim strName as String

To assign a value to a variable, you use the equal sign:

strName = "Fred Smith"

Putting this in a procedure looks like this:

Sub strExample()
'declare the string
   Dim strName as string
'populate the string
    strName = "Fred Smith"
'show the message box
   MsgBox strname
End Sub

If you run the code above, the following message box will be shown.

Fixed String Variable

There are actually 2 types of string variables – fixed and variable.

The “variable” string variable (shown in the previous example) allows your string to be any length. This is most common.

The “fixed” string variable defines the size of the string. A fixed string can hold up to 65,400 characters.

Dim strName as string *20

When you define a fixed variable, the number of characters in the variable is locked in place, even if you use fewer characters.

Notice the spaces in the graphic below – the variable has place holders for the rest of the characters in the string as ‘Fred Smith’ is less than 20 characters.

However, if you have declared a string without specifying the length, then the string will only hold as many characters as are passed to it.

Declare String Variable at Module or Global Level

In the previous example, you declared the String variable within a procedure. Variables declared with a procedure can only be used within that procedure.

Instead, you can declare String variables at the module or global level.

Module Level

Module level variables are declared at the top of code modules with the Dim statement.

These variables can be used with any procedure in that code module.

Global Level

Global level variables are also declared at the top of code modules. However, instead of using the Dim statement, you use the Public statement to indicate that the string variable is available to be used throughout your VBA Project.

Public strName as String

If  you declared the string variable at a module level and used in a different module, an error would occur.

However, if you use the Public keyword to declare the string variable, the error would not occur and the procedure would run perfectly.

Convert Values stored as String

There may be a time when you have values in Excel that are stored as text – for example, you may have imported a CSV file which may have brought in text instead of numbers.

Note that the value in A1 is left-aligned, indicating a text value.

You can use a VBA Function can be used to convert these numbers to text

Sub ConvertValue()
'populate the string
    strQty = Range("A1")
'populate the double with the string
    dblQty = strQty
'populate the range with the number
    Range("A1") = dblQty
End Sub

Once you run the code, the number will move to the right-indicating that it is now stored as a number.

This is particularly useful when you loop through a large range of cells.

Sub ConvertValue()
    Dim strQty As String, dblQty As Double
    Dim rw As Integer, i As Integer
'count the rows to convert
    rw = Range("A1", Range("A1").End(xlDown)).Rows.Count
'loop through the cells and convert each one to a number
    For i = 0 To rw – 1
'populate the string
        strQty = Range("A1").Offset(i, 0)
'populate the double with the string
        dblQty = strQty
'populate the range with the number
        Range("A1").Offset(i, 0) = dblQty
    Next i
End Sub

The result will be that all the cells are then converted to numbers

Convert String Stored as Values

Similarly, there might be values that you need to convert from a string to a value – for example, if you require a leading zero on a telephone number.

Sub ConvertString()
    Dim strPhone As String, dblPhone As Double
    Dim rw As Integer, i As Integer
'count the rows to convert
    rw = Range("A1", Range("A1").End(xlDown)).Rows.Count
'loop through the cells and convert each one to a number
    For i = 0 To rw – 1
'populate the string
        dblPhone = Range("A1").Offset(i, 0)
'populate the double with the string
        strPhone = "'0" & dblPhone
'populate the range with the number
        Range("A1").Offset(i, 0) = strphone
    Next i
End Sub

Note that you need to  begin the text string with an apostrophe (‘), before the zero in order to tell Excel to enter the value as string.