ChrB$ Function

Returns a String containing the character associated with the specified ANSI character code. The dollar sign suffix ($) explicitly indicates that this function returns a String type (not a Variant), and the "B" suffix indicates this is the byte (ANSI) version.

Syntax

ChrB$(charcode)

Parameters

• charcode: Required. Long value that identifies a character in the ANSI character set. Valid values are 0-255. For values outside this range, an error occurs.

Return Value

Returns a String containing the single byte character corresponding to the specified ANSI code. The return value is always a String type (never Variant), and represents a single-byte character from the ANSI character set.

Remarks

• The ChrB$ function combines the behavior of ChrB (byte character) with the $ suffix (explicit String return type).
• Valid range: 0-255 (Error 5 "Invalid procedure call or argument" for values outside range).
• ChrB$(0) returns a null character.
• ChrB$(13) returns carriage return (vbCr).
• ChrB$(10) returns line feed (vbLf).
• ChrB$(9) returns tab character (vbTab).
• Values 0-31 are non-printable control characters.
• Values 32-126 are standard printable ASCII characters.
• Values 127-255 depend on the system code page (often Windows-1252 in VB6).
• The inverse function is AscB, which returns the numeric byte value of a character.
• For better performance when you know the result is a string, use ChrB$ instead of ChrB.

Common Character Codes

Typical Uses

1. Building ANSI strings - Construct strings from byte values
2. Line breaks - Insert carriage returns and line feeds
3. Special characters - Add tabs, quotes, and other special characters
4. Byte-level operations - Work with binary data or legacy file formats
5. ANSI text generation - Create strings for systems expecting ANSI encoding
6. Legacy protocol support - Work with older communication protocols
7. Control characters - Generate non-printable control characters

Basic Examples

' Example 1: Get character from code
Dim ch As String
ch = ChrB$(65)  ' Returns "A"

' Example 2: Lowercase letter
Dim lower As String
lower = ChrB$(97)  ' Returns "a"

' Example 3: Special character
Dim space As String
space = ChrB$(32)  ' Returns " "

' Example 4: Line break
Dim msg As String
msg = "Line 1" & ChrB$(13) & ChrB$(10) & "Line 2"

Common Patterns

Multi-line Strings

Function CreateMultiLine() As String
Dim result As String
result = "First Line" & ChrB$(13) & ChrB$(10)
result = result & "Second Line" & ChrB$(13) & ChrB$(10)
result = result & "Third Line"
CreateMultiLine = result
End Function

Tab-Separated Values

Function CreateTSV(col1 As String, col2 As String, col3 As String) As String
CreateTSV = col1 & ChrB$(9) & col2 & ChrB$(9) & col3
End Function

Build String from Byte Array

Function BytesToString(bytes() As Byte) As String
Dim i As Integer
Dim result As String
For i = LBound(bytes) To UBound(bytes)
result = result & ChrB$(bytes(i))
Next i
BytesToString = result
End Function

Quote in String

Function AddQuotes(text As String) As String
AddQuotes = ChrB$(34) & text & ChrB$(34)
End Function

Null-Terminated String

Function CreateNullTerminated(text As String) As String
CreateNullTerminated = text & ChrB$(0)
End Function

ANSI Protocol Message

Function CreateProtocolMessage(msgType As Byte, data As String) As String
Dim msg As String
' SOH (Start of Header)
msg = ChrB$(1)
' Message type
msg = msg & ChrB$(msgType)
' STX (Start of Text)
msg = msg & ChrB$(2)
' Payload
msg = msg & data
' ETX (End of Text)
msg = msg & ChrB$(3)
CreateProtocolMessage = msg
End Function

Generate Alphabet

Function GenerateAlphabet() As String
Dim i As Integer
Dim result As String
For i = 65 To 90
result = result & ChrB$(i)
Next i
GenerateAlphabet = result  ' Returns "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
End Function

CSV Field with Quotes

Function QuoteCSVField(field As String) As String
Dim quoted As String
' Replace " with ""
quoted = Replace(field, ChrB$(34), ChrB$(34) & ChrB$(34))
QuoteCSVField = ChrB$(34) & quoted & ChrB$(34)
End Function

Password Mask

Function MaskPassword(length As Integer) As String
Dim i As Integer
Dim result As String
For i = 1 To length
result = result & ChrB$(42)  ' Asterisk
Next i
MaskPassword = result
End Function

Character Range

Function GetPrintableChars() As String
Dim i As Integer
Dim result As String
For i = 32 To 126
result = result & ChrB$(i)
Next i
GetPrintableChars = result
End Function

Related Functions

• ChrB: Returns byte character as Variant instead of String
• Chr$: Returns ANSI/Unicode character (system dependent)
• ChrW$: Returns Unicode character (2 bytes)
• AscB: Returns byte value of first byte in string (inverse of ChrB$)
• AscB$: Not a valid function (there is no AscB$)

Error Handling

Function SafeChrB(code As Long) As String
On Error Resume Next
SafeChrB = ChrB$(code)
If Err.Number <> 0 Then
SafeChrB = ""
Err.Clear
End If
End Function

Performance Considerations

• ChrB$ is slightly more efficient than ChrB because it avoids Variant overhead
• For building strings from many bytes, consider using a buffer or byte array
• Concatenating many ChrB$ calls can be slow; use arrays and Join for better performance
• When working with large amounts of byte data, consider String function or byte arrays

Best Practices

1. Use named constants for common control characters instead of magic numbers
2. Validate character codes are in the range 0-255 before calling ChrB$
3. Use ChrB$ for ANSI/byte operations, ChrW$ for Unicode operations
4. Document when using non-printable characters (codes 0-31)
5. Consider code page issues when working with extended ANSI (128-255)
6. Use vbCrLf constant instead of ChrB$(13) & ChrB$(10) when possible
7. Prefer ChrB$ over ChrB when you need a String result

Limitations

• Limited to character codes 0-255 (use ChrW$ for full Unicode support)
• Character interpretation depends on system code page for values 128-255
• Does not validate that the resulting character is printable
• No direct support for multi-byte Unicode characters