program recursion;{
    $APPTYPE CONSOLE}var  sourcestr, searchstr, replacestr: string;  i: Integer;begin  Write('源字符串:');  Readln(sourcestr);  Write('查找字符串:');  Readln(searchstr);  Write('替换字符串:');  Readln(replacestr);  {
    递归替换字符串中的字符}  i := Pos(searchstr, sourcestr);  while i <> 0 do  begin    Delete(sourcestr, i, Length(searchstr));    Insert(replacestr, sourcestr, i);    i := Pos(searchstr, sourcestr);  end;  Writeln(sourcestr);  readln;end.

效果如下:

看来还是得了解基本的东西,不然看啥都像天书…