以下是在网上找到的“通配符查找函数”,试了试挺好,没发现有问题,
但是由于水平太低,理解不了,请高手给加上注释,并说明一下原理,
如是石家庄附近的朋友,我请客!!!(前几天请教问题我就有请客的打算,
可惜高手们都不赏脸。)
(为和SQL一致,此函数我改一下,支持%和_)
function MaskMatch(const aPattern, aSource: string): Boolean;
var
StringPtr, PatternPtr: PChar;
StringRes, PatternRes: PChar;
begin
Result := False;
StringPtr := PChar(UpperCase(aSource));
PatternPtr := PChar(UpperCase(aPattern));
StringRes := nil;
PatternRes := nil;
repeat
repeat // ohne vorangegangenes "%"
case PatternPtr^ of
#0 : begin
Result := StringPtr^ = #0;
if Result or (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
Break;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
if StringPtr^ = #0 then Exit;
if StringPtr^ <> PatternPtr^ then
begin
if (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end else
begin
Inc(StringPtr);
Inc(PatternPtr);
end;
end;
end;
until False;repeat // mit vorangegangenem "%"
case PatternPtr^ of
#0 : begin
Result := True;
Exit;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
repeat
if StringPtr^ = #0 then Exit;
if StringPtr^ = PatternPtr^ then Break;
Inc(StringPtr);
until False;
Inc(StringPtr);
StringRes := StringPtr;
Inc(PatternPtr);
Break;
end;
end;
until False;
until False;
end;
但是由于水平太低,理解不了,请高手给加上注释,并说明一下原理,
如是石家庄附近的朋友,我请客!!!(前几天请教问题我就有请客的打算,
可惜高手们都不赏脸。)
(为和SQL一致,此函数我改一下,支持%和_)
function MaskMatch(const aPattern, aSource: string): Boolean;
var
StringPtr, PatternPtr: PChar;
StringRes, PatternRes: PChar;
begin
Result := False;
StringPtr := PChar(UpperCase(aSource));
PatternPtr := PChar(UpperCase(aPattern));
StringRes := nil;
PatternRes := nil;
repeat
repeat // ohne vorangegangenes "%"
case PatternPtr^ of
#0 : begin
Result := StringPtr^ = #0;
if Result or (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
Break;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
if StringPtr^ = #0 then Exit;
if StringPtr^ <> PatternPtr^ then
begin
if (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end else
begin
Inc(StringPtr);
Inc(PatternPtr);
end;
end;
end;
until False;repeat // mit vorangegangenem "%"
case PatternPtr^ of
#0 : begin
Result := True;
Exit;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
repeat
if StringPtr^ = #0 then Exit;
if StringPtr^ = PatternPtr^ then Break;
Inc(StringPtr);
until False;
Inc(StringPtr);
StringRes := StringPtr;
Inc(PatternPtr);
Break;
end;
end;
until False;
until False;
end;
var
StringPtr, PatternPtr: PChar;
StringRes, PatternRes: PChar;
begin
Result := False;
StringPtr := PChar(UpperCase(aSource)); //都转换成大写
PatternPtr := PChar(UpperCase(aPattern));
StringRes := nil;
PatternRes := nil;
repeat
repeat // ohne vorangegangenes "%"
case PatternPtr^ of
#0 : begin
Result := StringPtr^ = #0; //返回值等于 (StringPtr^ = #0 )
if Result or (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
Break;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
if StringPtr^ = #0 then Exit;
if StringPtr^ <> PatternPtr^ then
begin
if (StringRes = nil) or (PatternRes = nil) then Exit;
StringPtr := StringRes;
PatternPtr := PatternRes;
Break;
end else
begin
Inc(StringPtr);
Inc(PatternPtr);
end;
end;
end;
until False; repeat // mit vorangegangenem "%"
case PatternPtr^ of
#0 : begin
Result := True;
Exit;
end;
'%': begin
Inc(PatternPtr);
PatternRes := PatternPtr;
end;
'_': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(PatternPtr);
end;
else begin
repeat
if StringPtr^ = #0 then Exit;
if StringPtr^ = PatternPtr^ then Break;
Inc(StringPtr);
until False;
Inc(StringPtr);
StringRes := StringPtr;
Inc(PatternPtr);
Break;
end;
end;
until False;
until False;
end;