Blitz3D+ Command Reference

Chr$ ( ascii )

Parameters

ascii - the character code to convert

Description

Returns a one-character string with the given character code.

Chr( 65 ) is "A". It is the inverse of Asc.

Chr is how you get at characters you cannot type into a string literal. Chr( 34 ) gives you a double quote, Chr( 9 ) a tab, and Chr( 13 )+Chr( 10 ) a Windows line break for writing to a file. It also builds characters that live beyond the letters and digits in your font sheet - box-drawing pieces, arrows, or a degrees sign.

The other everyday use is arithmetic on letters: Chr( Asc( "A" )+n ) walks through the alphabet, which is handy for labelling save slots, generating level codes, or stepping a cipher.

Only the low eight bits of the value are used, so codes wrap round outside 0 to 255 rather than producing a multi-byte character.

See also: Asc, String, Mid, Str.

Example

; Chr Example
; -----------

; Chr$ converts an ASCII code back into a one-character string.
; It is the reverse of Asc.

Print "Chr$(65) = "+Chr$(65)+"  (65 is the code for A)"
Print ""

; Build the letter row for a high-score name-entry screen
alphabet$=""
For code=65 To 90
    alphabet$=alphabet$+Chr$(code)
Next
Print "Name-entry letters: "+alphabet$

; Chr$(34) is the double-quote - the only way to put one in a string
Print ""
Print "The pilot said "+Chr$(34)+"Fire!"+Chr$(34)

; Round trip: Asc undoes Chr$
Print ""
Print "Chr$(90) = "+Chr$(90)+" and Asc('Z') = "+Asc("Z")

Print ""
Print "Press any key to close the example"
WaitKey

End

Index