检查目录是否可读

Question

如何检查目录是否只读？

Answer 1

您可以使用FileGetAttr函数并检查faReadOnly标志是否已设置。

试试这个代码

function DirIsReadOnly(Path:string):Boolean; 
var 
attrs : Integer; 
begin 
attrs := FileGetAttr(Path); 
Result := (attrs and faReadOnly) > 0; 
end; 

Answer 2

在Windows API的方式，它是：

fa := GetFileAttributes(PChar(FileName)) 
if (fa and FILE_ATTRIBUTE_DIRECTORY <> 0) and (fa and FILE_ATTRIBUTE_READONLY <> 0) then 
    ShowMessage('Directory is read-only'); 

Answer 3

测试，如果该目录的属性是R/O只是答案的一部分。由于访问权限，您可以轻松地拥有一个仍然无法写入的R/W目录。

最好的方式来检查，如果你可以写一个目录与否是 - 试试：

FUNCTION WritableDir(CONST Dir : STRING) : BOOLEAN; 
    VAR 
    FIL : FILE; 
    N : STRING; 
    I : Cardinal; 

    BEGIN 
    REPEAT 
     N:=IncludeTrailingPathDelimiter(Dir); 
     FOR I:=1 TO 250-LENGTH(N) DO N:=N+CHAR(RANDOM(26)+65) 
    UNTIL NOT FileExists(N); 
    Result:=TRUE; 
    TRY 
     AssignFile(FIL,N); 
     REWRITE(FIL,1); 
     Result:=FileExists(N); // Not sure if this is needed, but AlainD says so :-) 
    EXCEPT 
     Result:=FALSE 
    END; 
    IF Result THEN BEGIN 
     CloseFile(FIL); 
     ERASE(FIL) 
    END 
    END; 

Answer 4

版本HeartWare给是好的，但包含了两个错误。这个修改后的版本工作更可靠，并具有注释来解释正在发生的事情：

function IsPathWriteable(const cszPath: String) : Boolean; 
var 
    fileTest: file; 
    szFile: String; 
    nChar: Cardinal; 
begin 
    // Generate a random filename that does NOT exist in the directory 
    Result := True; 
    repeat 
     szFile := IncludeTrailingPathDelimiter(cszPath); 
     for nChar:=1 to (250 - Length(szFile)) do 
      szFile := (szFile + char(Random(26) + 65)); 
    until (not FileExists(szFile)); 

    // Attempt to write the file to the directory. This will fail on something like a CD drive or 
    // if the user does not have permission, but otherwise should work. 
    try 
     AssignFile(fileTest, szFile); 
     Rewrite(fileTest, 1); 

     // Note: Actually check for the existence of the file. Windows may appear to have created 
     // the file, but this fails (without an exception) if advanced security attibutes for the 
     // folder have denied "Create Files/Write Data" access to the logged in user. 
     if (not FileExists(szFile)) then 
      Result := False; 
    except 
     Result := False; 
    end; 

    // If the file was written to the path, delete it 
    if (Result) then 
     begin 
     CloseFile(fileTest); 
     Erase(fileTest); 
     end; 
end;