function StringReplace (const S, OldPattern, NewPattern: string; Flags: TReplaceFlags): string; rfReplaceAll:全部替换 rfIgnoreCase:忽略大小写 For Example: var aStr: String; begin aStr := 'This is a book, not a pen!'; ShowMessage(StringReplace (aStr, 'a', 'two', []));//This is two book, not a pen!只替换了第一个符合的字 ShowMessage(StringReplace (aStr, 'a', 'two', [rfReplaceAll]));//This is two book, not two pen!替换了所有符合的字 aStr := 'This is a book, not A pen!'; ShowMessage(StringReplace (aStr, 'a', 'two', [rfReplaceAll]));//This is two book, not A pen!只替换了符合的字(小写a) ShowMessage(StringReplace (aStr, 'a', 'two', [rfReplaceAll, rfIgnoreCase]));//This is two book, not two pen!不管大小写替换了所有符合的字 end;