Bold text in a Concatenate formula - vba

Question

I would like to be able to make one or two specific words bold in my sentence when using a concatenate formula. An example is shown below.
The first sentence is using the concatenate formula. The second sentence is manually typed and formatted. Is there a way to have this formatting in the concatenate formula without having to do it manually every time?
Please note that this is just an example and I may need to use it to make a string of three consecutive words bold in a different sentence. If a general rule was provided that I can work with going forwards that would be great!
I am somewhat proficient with formulae but have never used VBA. However I suspect the solution for this problem may only be available using VBA. Please be considerate if a VBA solution is required as it'll take some time and effort for me to start-up and understand.
Thanks for your time and help.
Edit:
Public Sub ExampleConcatenate()
Dim str1 As String, str2 As String, str3 As String, str4 As String, str5 As String, str6 As String
str1 = "First string "
str2 = "Second string "
str3 = "Third string"
str4 = "Fourth string "
str5 = "Fifth string "
str6 = "Sixth string"
Range("A1").Value = str1 & str2 & str3 & str4 & str5 & str6 'concatenate strings
'format bold starts 1 character after str1 and is as long as str2
Range("A1").Characters(Start:=Len(str1) + 1, Length:=Len(str2)).Font.Bold = True
End Sub
How would I further extend the final part to make the fourth and sixth strings bold?

Answer 1

You cannot format individual characters in a cell text if that cell contains a formula.
Excel doesn't support that.
Workaround
The only workaround is to write that cell text as constant text (with VBA) instead of a formula (if that meets your requirement).
Then you can format individual characters with:
Range("A1").Characters(Start:=1, Length:=10).Font.Bold = True
So to partly format a string you could adjust the following example
Public Sub ExampleConcatenate()
Dim str1 As String, str2 As String, str3 As String
str1 = "First string "
str2 = "Second string "
str3 = "Third string"
Range("A1").Value = str1 & str2 & str3 'concatenate strings
'format bold starts 1 character after str1 and is as long as str2
Range("A1").Characters(Start:=Len(str1) + 1, Length:=Len(str2)).Font.Bold = True
End Sub
For more sub strings it would be easier to use an array.
Public Sub ExampleConcatenate()
Dim SubStrings As Variant
SubStrings = Array("First string ", _
"Second string ", _
"Third string ", _
"Fourth string ", _
"Fifth string ", _
"Sixth string")
Range("A1").Value = Join(SubStrings, "")
'Note array counting starts with 0 not 1 so "First string" is SubStrings(0)
'format bold starts 1 character after str1 and is as long as str2
Range("A1").Characters(Start:=Len(SubStrings(0)) + 1, Length:=Len(SubStrings(1))).Font.Bold = True
'format sub string 4
Range("A1").Characters(Start:=Len(SubStrings(0)) + Len(SubStrings(1)) + Len(SubStrings(2)) + 1, Length:=Len(SubStrings(3))).Font.Bold = True
'format sub string 6
Range("A1").Characters(Start:=Len(SubStrings(0)) + Len(SubStrings(1)) + Len(SubStrings(2)) + Len(SubStrings(3)) + Len(SubStrings(4)) + 1, Length:=Len(SubStrings(5))).Font.Bold = True
End Sub

Answer 2

While you cannot make text bold within a formula, you CAN make text u̲n̲d̲e̲r̲l̲i̲n̲e̲d̲. No VBA needed; the magic here is unicode special characters.
After each character that you want underlined, insert the unicode combining low line character U+0332. You can copy-paste it from that site, or use this site to apply it after each character in the text you want to print.
See the example below to apply it to an arbitrary word in a text string.
=LEFT(B2,B6)&TEXTJOIN("̲",TRUE,MID(B2,ROW(OFFSET(A1,B6,0,B7)),1))&MID(B2,B6+B7,LEN(B2))
Starting with LEFT(B2,B6) returns up until the fifth word. Similarly MID(B2,B6+B7,LEN(B2)) returns everything after the fifth word.
The real magic happens with TEXTJOIN(). This function repeats the first argument in between each element of the reference in the third argument. Notice the underline is combined with the double quote character when rendered in the equation bar. The third argument uses MID() to return the fifth word, but with each letter a separate reference so that it is combined with the combining low line character by TEXTJOIN(). Splitting the fifth word by each character is achieved by passing an array as the second argument of MID() using ROW(OFFSET()) to count from the start to the end of the fifth word.