Fast and reliable handlers for reading from and writing to text files. More or less standard. Should work under any version of AppleScript. All parameters are strings.
No coercions are performed, so things other than text can be written & read, but I've only tested them with strings. Some versions of AS are buggy with other data types - like lists - so use them with caution. This also means that pathString must be a string, not an alias or file specification.
Read the data fork of a file - a simple read.
USAGE: set fileContents to simpleFileRead from "Mac HD:Desktop Folder:myTestFile"
--> anything - whatever is in the file
Input: string - full path to an existing file.
Output: string - the contents of the file's data fork.
Error: passes the error if it can't successfully read the file for any reason.
-- simpleRead -- by Richard Morton 2001
-- Read a file, returning its contents. Pass a valid path string.
to simpleRead from pathString
try
set ofaNum to open for access file pathString
set fileData to read ofaNum
close access ofaNum
on error errMsg number errNum
try
close access file pathString
on error
end try
error errMsg number errNum
end try
return fileData
end simpleRead
Write a string to a text file, creating if required & overwriting an existing file, if found. Pass a path string and the string (text) to write.
USAGE: overWriteFile at "Mac HD:Desktop Folder:myTestFile" from "Hello World"
--> "Mac HD:Desktop Folder:myTestFile"
Input:
pathString string - full valid path including legal file name.
writeString string - some other data types are possible, none guaranteed.
Output: string (full path to the file) - data will be written to the specified file which will be created if required, overwritten if existing.
Error: passes the error if it can't successfully write a file for any reason.
-- overWriteFile -- by Richard Morton 2001
-- Write to a file, overwriting existing contents, creating file
-- if required. Pass a valid path string and the string to write.
to overWriteFile at pathString from writeString
try
set ofaNum to open for access file pathString with write permission
set eof of ofaNum to 0
write writeString to ofaNum
close access ofaNum
return pathString
on error errMsg number errNum
try
close access file pathString
on error
end try
error errMsg number errNum
end try
end overWriteFile
Write a string to a text file, creating it if required & appending to the contents of an existing file, if found. Pass a valid path string and the string (text) to write.
USAGE: As above
Input:
pathString string - full valid path including legal file name.
writeString string - some other data types are possible, none guaranteed.
Output: string (full path to the file) - data will be written to the specified file which will be created if required, appended to if existing.
Error: passes the error if it can't successfully write a file for any reason.
-- writeWithAppend -- by Richard Morton 2001
-- Write to a file, appending to existing contents, creating file
-- if required. Pass a valid path string and the string to write.
to writeWithAppend at pathString from writeString
try
set ofaNum to open for access file pathString with write permission
write writeString to ofaNum starting at eof
close access ofaNum
return pathString
on error errMsg number errNum
try
close access file pathString
on error
end try
error errMsg number errNum
end try
end writeWithAppend
Reads the first n bytes of a file. Use it for making sure you have the right file. Pass a path string to an existing file & the number of bytes to read.
USAGE: set fileHeader to readFirstBytes from "Mac HD:Desktop Folder:myTestFile" for 5
--> string - the first 5 bytes of the file
Input:
pathString string - full path to an existing file.
numBytes integer - the number of bytes to read from the beginning of the file.
Output: string - the bytes that were read from the file's data fork.
Error: passes the error if it can't successfully read the file for any reason.
-- readFirstBytes -- by Richard Morton 2001
-- Read the first n bytes of a file. Use to identify files. Pass a
-- path string to an existing file and the number of bytes to read.
on readFirstBytes from pathString for numBytes
try
set ofaNum to open for access file pathString
set fileData to read ofaNum for numBytes
close access ofaNum
on error errMsg number errNum
try
close access file pathString
on error
end try
error errMsg number errNum
end try
return fileData
end readFirstBytes
The FooDoo Lounge is Copyright © Richard Morton 2002-2005
|| url: http://www.foodoo.sunreal.com.au/code/file_io.html
|| created: 4-Aug-03, 10:11 PM; updated: 4-Aug-03, 11:55 AM
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