对于常用的SQL语句，有时为了规整，必须让关键字大写，但对有的不规范的，我们可以用正则表达式修改为大写，具体步骤为：
1.定义要大写的关键字
const
sMatch: array[1..34] of string = ('select', 'case', 'begin', 'and', 'from', 'where', 'update', 'delete',
'left', 'join', 'full', 'right', 'inner', 'outer', 'declare', 'set', 'distinct', 'if', 'is', 'null','order',
'group', 'by', 'asc', 'desc', 'or', 'exists', 'having', 'sum', 'count', 'average', 'ave', 'raise', 'error');
2.定义规则
for i := Low(sMatch) to High(sMatch) do
if Rgr.Exec(Memo1.Text) then
repeat
str := Rgr.Match[1];
str1 := StringReplace(str1,str,UpperCase(str),[rfReplaceAll]);
until not Rgr.ExecNext;
Memo2.Text :=str1;
整个代码为：
1 var
2 i: Integer;
3 Rgr: TRegExpr;
4 sExpr,str,str1: string;
5 begin
6 Memo1.Lines.Clear;
7 Memo1.Lines.Text := 'select * from delphi WHERE id=1 and kind=3' + #10#13
8 + ' ordER By id';
9 Rgr := TRegExpr.Create;
10 try
11 Rgr.ModifierI := True;
12 for i := Low(sMatch) to High(sMatch) do
13 sExpr := sExpr + sMatch[i] + '|';
14 sExpr := '(' + Copy(sExpr, 1, Length(sExpr) - 1) + ')';
15 Rgr.Expression :=sExpr;
16 str1 :=Memo1.Text;
17 if Rgr.Exec(Memo1.Text) then
18 repeat
19 str := Rgr.Match[1];
20 str1 := StringReplace(str1,str,UpperCase(str),[rfReplaceAll]);
21 until not Rgr.ExecNext;
22 Memo2.Text :=str1;
23 finally
24 Rgr.Free;
25 end;
26 end;