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manipulating_20filenames_20and_20pathnames

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manipulating_20filenames_20and_20pathnames [2018/03/31 13:19] – external edit 127.0.0.1manipulating_20filenames_20and_20pathnames [2024/01/05 00:22] (current) – external edit 127.0.0.1
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 ===== Root directory ===== ===== Root directory =====
 **FNf_root()** extracts the root directory from the supplied path. You can't just look for a colon specifying a drive, as the program may have been run with a Uniform Naming Convention path (see [[http://en.wikipedia.org/wiki/Path_(computing)#Uniform_Naming_Convention|Wikipedia]]). Also, the path may be surrounded by quotes, which have to be taken care of.\\ \\  FNf_root() will return as per the following examples:\\  **FNf_root()** extracts the root directory from the supplied path. You can't just look for a colon specifying a drive, as the program may have been run with a Uniform Naming Convention path (see [[http://en.wikipedia.org/wiki/Path_(computing)#Uniform_Naming_Convention|Wikipedia]]). Also, the path may be surrounded by quotes, which have to be taken care of.\\ \\  FNf_root() will return as per the following examples:\\ 
-      FNf_root("C:\Documents and Settings\jgh\Admin")   -> "C:" +<code bb4w> 
-      FNf_root("H:\Apps")                               -> "H:" +      FNf_root("C:\Documents and Settings\jgh\Admin")  *| -> "C:" 
-      FNf_root("\\datastore\Tools\Admin")               -> "\\datastore" +      FNf_root("H:\Apps")                              *| -> "H:" 
-      FNf_root("X:")                                    -> "X:"+      FNf_root("\\datastore\Tools\Admin")              *| -> "\\datastore" 
 +      FNf_root("X:")                                   *| -> "X:" 
 +</code>
 You could then do, for example:\\  You could then do, for example:\\ 
 +<code bb4w>
         PROCcopyfiles(FNf_root(indir$)+"\Data","D:\Backup","*.*")         PROCcopyfiles(FNf_root(indir$)+"\Data","D:\Backup","*.*")
 +</code>
 \\  \\ 
 ===== Extracting leafname ===== ===== Extracting leafname =====
 **FNf_leaf()** will scan through a fully-qualified pathname to find just the leafname - the final part of the path.\\  **FNf_leaf()** will scan through a fully-qualified pathname to find just the leafname - the final part of the path.\\ 
 +<code bb4w>
         DEF FNf_leaf(A$)         DEF FNf_leaf(A$)
         LOCAL A%:REPEAT:A%=INSTR(A$,"\"):IFA%:A$=MID$(A$,A%+1)         LOCAL A%:REPEAT:A%=INSTR(A$,"\"):IFA%:A$=MID$(A$,A%+1)
         UNTILA%=0:=A$         UNTILA%=0:=A$
 +</code>
 For example, **FNf_leaf("H:\Apps\Admin\Startup.exe")** returns **"Startup.exe"**.\\ \\  For example, **FNf_leaf("H:\Apps\Admin\Startup.exe")** returns **"Startup.exe"**.\\ \\ 
 ===== Removing leafname ===== ===== Removing leafname =====
 **FNf_path()** will remove the leafname, keeping just the pathname. For example:\\  **FNf_path()** will remove the leafname, keeping just the pathname. For example:\\ 
 +<code bb4w>
         DEF FNf_path(A$):IFINSTR(A$,"\")=0:=A$         DEF FNf_path(A$):IFINSTR(A$,"\")=0:=A$
         LOCAL A%:REPEATB%=A%:A%=INSTR(A$,"\",A%+1):UNTILA%=0:=LEFT$(A$,B%)         LOCAL A%:REPEATB%=A%:A%=INSTR(A$,"\",A%+1):UNTILA%=0:=LEFT$(A$,B%)
 +</code>
 This lets you use code such as:\\  This lets you use code such as:\\ 
 +<code bb4w>
       IF out$="" THEN out$=FNf_path(in$)+"output.txt"       IF out$="" THEN out$=FNf_path(in$)+"output.txt"
 +</code>
 \\  \\ 
 ===== Removing filename extension ===== ===== Removing filename extension =====
 **FNf_noext()** will remove an extension from a pathname. Note that you cannot just remove the last four characters, as the extension is not guaranteed to be four characters (eg, ".c"), nor can you simply search for a ".", as the path may have multiple "."s in it (eg **"C:\index.dat\20090721\thumb.db"** or even **"Version1.00\data.file.txt"**).\\  **FNf_noext()** will remove an extension from a pathname. Note that you cannot just remove the last four characters, as the extension is not guaranteed to be four characters (eg, ".c"), nor can you simply search for a ".", as the path may have multiple "."s in it (eg **"C:\index.dat\20090721\thumb.db"** or even **"Version1.00\data.file.txt"**).\\ 
 +<code bb4w>
         DEF FNf_ext(A$):IFINSTR(A$,".")=0:=""         DEF FNf_ext(A$):IFINSTR(A$,".")=0:=""
         LOCAL A%:A%=LENA$+1:REPEATA%=A%-1:UNTIL INSTR(".:\",MID$(A$,A%,1))         LOCAL A%:A%=LENA$+1:REPEATA%=A%-1:UNTIL INSTR(".:\",MID$(A$,A%,1))
         IF MID$(A$,A%,1)=".":=MID$(A$,A%) ELSE =""         IF MID$(A$,A%,1)=".":=MID$(A$,A%) ELSE =""
 +</code>
 You can then use this to do, for example:\\  You can then use this to do, for example:\\ 
 +<code bb4w>
       PROCBMP_toGIF(bmpfile$,FNf_noext(bmpfile$)+".gif")       PROCBMP_toGIF(bmpfile$,FNf_noext(bmpfile$)+".gif")
 +</code>
 Note that filenames similar to **".htaccess"** are seen as being all extension and no name.\\ \\  Note that filenames similar to **".htaccess"** are seen as being all extension and no name.\\ \\ 
 ===== Finding filename extension ===== ===== Finding filename extension =====
 **FNf_ext()** will scan through a fully-qualified pathname to find the extension. As with **FNf_noext()**, you cannot just use the last four characters.\\  **FNf_ext()** will scan through a fully-qualified pathname to find the extension. As with **FNf_noext()**, you cannot just use the last four characters.\\ 
 +<code bb4w>
         DEF FNf_noext(A$):IFINSTR(A$,".")=0:=A$         DEF FNf_noext(A$):IFINSTR(A$,".")=0:=A$
         LOCAL A%:A%=LENA$+1:REPEATA%=A%-1:UNTIL INSTR(".:\",MID$(A$,A%,1))         LOCAL A%:A%=LENA$+1:REPEATA%=A%-1:UNTIL INSTR(".:\",MID$(A$,A%,1))
         IFMID$(A$,A%,1)=".":=LEFT$(A$,A%-1) ELSE =A$         IFMID$(A$,A%,1)=".":=LEFT$(A$,A%-1) ELSE =A$
 +</code>
 You can then use this to do, for example:\\  You can then use this to do, for example:\\ 
 +<code bb4w>
       runapp$=FNMime_Type(FNf_ext(file$))       runapp$=FNMime_Type(FNf_ext(file$))
 +</code>
 \\  \\ 
 ===== Ensuring full absolute pathnames ===== ===== Ensuring full absolute pathnames =====
  It is good practice for programs to access files via fully-specified paths, yet it can also be useful for programs to be able to access certain files relative to some path, such as the directory the program is running in. **FNf_fullpath()** will take a path and a filename and return the full path of a relative filename.\\   It is good practice for programs to access files via fully-specified paths, yet it can also be useful for programs to be able to access certain files relative to some path, such as the directory the program is running in. **FNf_fullpath()** will take a path and a filename and return the full path of a relative filename.\\ 
 +<code bb4w>
         DEF FNf_fullpath(path$,file$)         DEF FNf_fullpath(path$,file$)
         IF INSTR(file$,":")<>0 OR INSTR(file$,"\\")<>0:=file$         IF INSTR(file$,":")<>0 OR INSTR(file$,"\\")<>0:=file$
         IF RIGHT$(path$,1)<>"\":path$=path$+"\"         IF RIGHT$(path$,1)<>"\":path$=path$+"\"
         =path$+file$         =path$+file$
 +</code>
 It functions as in the following examples.\\  It functions as in the following examples.\\ 
-      FNf_fullpath("C:\EARS","DATA")            -> "C:\EARS\DATA" +<code bb4w> 
-      FNf_fullpath("C:\EARS","A:\INCOMING")     -> "A:\INCOMING" +      FNf_fullpath("C:\EARS","DATA")            *| -> "C:\EARS\DATA" 
-      FNf_fullpath("C:\EARS","\\system\backup") -> "\\system\backup"+      FNf_fullpath("C:\EARS","A:\INCOMING")     *| -> "A:\INCOMING" 
 +      FNf_fullpath("C:\EARS","\\system\backup") *| -> "\\system\backup" 
 +</code>
manipulating_20filenames_20and_20pathnames.1522502368.txt.gz · Last modified: 2024/01/05 00:17 (external edit)