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2个不错的通配符比较函数_Delphi教程_src119.com -

近日在和朋友讨论 MaskMatch 时偶得2个不错的算法。
函数1 只支持'*','?'模糊匹配。速度比采用递归算法的快近2倍，比TMask方法快很多。
函数2 完全支持正规表达式。速度于之前的相同。(不会正规表达式的朋友慎用)

// ===========================
// Funtion 1
// ===========================

// Check if the string can match the wildcard. It can be used for unicode strings as well!
// C: 2004-07-24 | M: 2004-07-24
function MaskMatch(co t aPattern, aSource: string): Boolea
var
StringPtr, Patter tr: PChar;
StringRes, PatternRes: PChar;
begin
Result := False;
StringPtr := PChar(U erCase(aSource));
Patter tr := PChar(U erCase(aPattern));
StringRes := nil;
PatternRes := nil;
repeat
repeat // ohne vorangegangenes "*"
case Patter tr^ of
#0 : begin
Result := StringPtr^ = #0;
if Result or (StringRes = nil) or (PatternRes = nil) then Exit;
tringPtr := StringRe
atter tr := PatternRe
reak;
end;
'*': begin
Inc(Patter tr);
atternRes := Patter tr;
reak;
end;
'?': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(Patter tr);
end;
else begin
if StringPtr^ = #0 then Exit;
if StringPtr^ < gt; Patter tr^ then
egin
if (StringRes = nil) or (PatternRes = nil) then Exit;
tringPtr := StringRe
atter tr := PatternRe
reak;
end else
egin
Inc(StringPtr);
Inc(Patter tr);
end;
end;
end;
until False;

repeat // mit vorangegangenem "*"
case Patter tr^ of
#0 : begin
Result := True;
Exit;
end;
'*': begin
Inc(Patter tr);
atternRes := Patter tr;
end;
'?': begin
if StringPtr^ = #0 then Exit;
Inc(StringPtr);
Inc(Patter tr);
end;
else begin
repeat
if StringPtr^ = #0 then Exit;
if StringPtr^ = Patter tr^ then Break;
Inc(StringPtr);
until False;
Inc(StringPtr);
tringRes := StringPtr;
Inc(Patter tr);
reak;
end;
end;
until False;
until False;
end;

// ===========================
// Funtion 2
// ===========================

function _MatchPattern(aPattern, aSource: PChar): Boolea
begin
Result := True;
while (True) do
begin
case aPattern[0] of
#0 : begin
//End of pattern reached.
Result := (aSource[0] = #0); //TRUE if end of aSource.
Exit;
end;

'*': begin //Match zero or more occurances of any char.
if (aPattern[1] = #0) then
egin
//Match any number of trailing chars.
Result := True;
Exit;
end else
Inc(aPattern);

while (aSource[0] < gt; #0) do
egin
//Try to match any su tring of aSource.
if (_MatchPattern(aSource, aPattern)) then
egin
Result := True;
Exit;
end;

//Continue testing next char...
Inc(aSource);
end;
end;

'?': begin //Match any one char.
if (aSource[0] = #0) then
egin
Result := False;
Exit;
end;

//Continue testing next char...
Inc(aSource);
Inc(aPattern);
end;

'[': begin //Match given set of chars.
if (aPattern[1] in [#0,'[',']']) then
egin
//Invalid Set - So no match.
Result := False;
Exit;
end;

if (aPattern[1] = '^') then
egin
//Match for exclusion of given set...
Inc(aPattern, 2);
Result := True;
while (aPattern[0] < gt; ']') do
egin
if (aPattern[1] = '-') then
egin
//Match char exclusion range.
if (aSource[0] >= aPattern[0]) and (aSource[0] <= aPattern[2]) then
egin
//Given char failed set exclusion range.
Result := False;
reak;
end else
Inc(aPattern, 3);
end else
egin
//Match individual char exclusion.
if (aSource[0] = aPattern[0]) then
egin
//Given char failed set element exclusion.
Result := False;
reak;
end else
Inc(aPattern);
end;
end;
end else
egin
//Match for inclusion of given set...
Inc(aPattern);
Result := False;
while (aPattern[0] < gt; ']') do
egin
if (aPattern[1] = '-') then
egin
//Match char inclusion range.
if (aSource[0] >= aPattern[0]) and (aSource[0] <= aPattern[2]) then
egin
//Given char matched set range inclusion.
// Continue testing...
Result := True;
reak;
end else
Inc(aPattern, 3);
end else
egin
//Match individual char inclusion.
if (aSource[0] = aPattern[0]) then
egin
//Given char matched set element inclusion.
// Continue testing...
Result := True;
reak;
end else
Inc(aPattern);
end;
end;
end;

if (Result) then
egin
//Match was found. Continue further.
Inc(aSource);
//Position Pattern to char after "]"
while (aPattern[0] < gt; ']') and (aPattern[0] < gt; #0) do Inc(aPattern);
if (aPattern[0] = #0) then
egin
//Invalid Pattern - mi ing "]"
Result := False;
Exit;
end else
Inc(aPattern);
end else
Exit;
end;

else begin //Match given single char.
if (aSource[0] < gt; aPattern[0]) then
egin
Result := False;
reak;
end;

//Continue testing next char...
Inc(aSource);
Inc(aPattern);
end;
end;
end;
end;

function MatchPattern(co t aPattern, aSource: string): Boolea
begin
Result := _MatchPattern(PChar(aPattern), PChar(aSource));
end;