function substr(var Source,sub,new:String):integer;
var
i,j,k:integer;
begin
i:=pos(sub,Source);
j:=length(sub);
k:=length(new);
if (i<1) or (j<1) or (k<1) then Result:=-1 //非法参数或未找到子串
else
begin
Delete(Source,i,j);
Insert(new,Source,i);
Result:=0;//替代成功
end;
end;//用法:abc efg" 被替换成"asd efg"
//var s:string;
//s:='abc efg';
//substr(s,'abc','asd');
//showmessage(s);
var
i,j,k:integer;
begin
i:=pos(sub,Source);
j:=length(sub);
k:=length(new);
if (i<1) or (j<1) or (k<1) then Result:=-1 //非法参数或未找到子串
else
begin
Delete(Source,i,j);
Insert(new,Source,i);
Result:=0;//替代成功
end;
end;//用法:abc efg" 被替换成"asd efg"
//var s:string;
//s:='abc efg';
//substr(s,'abc','asd');
//showmessage(s);
a: string;a := StringReplace("abc efg", 'bc', 'sd', [rfReplaceAll]);