WriteByte stream,byte
Parameters
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stream - a file stream opened for writing, or a TCP stream byte - value to write; only the low 8 bits (0-255) are stored |
Description
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Writes one byte (0-255) to a file or stream. A byte is 8 bits, so only values 0 to 255 store faithfully - anything else keeps just its low 8 bits (writing 256 stores 0, writing -1 stores 255). That is how integers work, not a bug. Since characters are single bytes, WriteByte can build a text file one character at a time (Asc gives you the byte for a character). When you have a lot of bytes to move, put them in a bank and use WriteBytes instead - one big write beats thousands of little ones. See also: ReadByte, WriteShort, WriteInt, WriteBytes. |
Example
; WriteByte Example ; ----------------- ; WriteByte stores a single byte (0 to 255); only the low ; 8 bits of the number are kept file=WriteFile("demo_bytes.dat") WriteByte file,65 WriteByte file,255 WriteByte file,256 WriteByte file,-1 CloseFile file Print "Wrote 4 bytes - demo_bytes.dat is "+FileSize("demo_bytes.dat")+" bytes" ; Read them back to see the wrap-around file=ReadFile("demo_bytes.dat") a=ReadByte(file) Print " 65 -> "+a+" (the ASCII code for "+Chr$(a)+")" Print " 255 -> "+ReadByte(file)+" (largest value a byte can hold)" Print " 256 -> "+ReadByte(file)+" (wrapped around to 0)" Print " -1 -> "+ReadByte(file)+" (wrapped around to 255)" CloseFile file ; Clean up the demo file DeleteFile "demo_bytes.dat" Print "Deleted demo_bytes.dat" Print "" Print "Press any key to close the example" WaitKey End
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