如何从 delphi 中某行之前删除文本

Question

<h1 class="tt">example</h1></div><div class="bl_la_main"><div class="divtext">

I am trying to remove everything before <div class="bl_la_main"> but keep everything after it.

Any help would be appreciated. Thanks

Answer 1

PS: Since I misunderstood the question, I first created the "take the before terms" function.

You can take it like this.

procedure TForm1.Button1Click(Sender: TObject);
var
 HTML: string;
begin
 HTML := '<h1 class="tt">example</h1></div><div class="bl_la_main"><div class="divtext">';
 Delete(HTML, Pos('<div class="bl_la_main">', HTML) - 1, Length(HTML) - Pos('<div class="bl_la_main">', HTML));
 ShowMessage(HTML);
end;

If we need to make it functional;

function parseHTML(html: string; substr: string): string;
begin
 Delete(HTML, Pos(substr, HTML) - 1, Length(HTML) - Pos(substr, HTML));
 Result := HTML;
end;

Use:

function parseHTML(html: string; substr: string): string;
begin
 Delete(HTML, Pos(substr, HTML) - 1, Length(HTML) - Pos(substr, HTML));
 Result := HTML;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
 HTML: string;
begin
 HTML := '<h1 class="tt">example</h1></div><div class="bl_la_main"><div class="divtext">';
 ShowMessage(parseHTML(HTML, '<div class="bl_la_main">'));
end;

Result:

<h1 class="tt">example</h1></div">

I created it separately, in a functional way to take both before and after.

function parseHTMLAfter(html: string; substr: string): string;
begin
 Delete(HTML, Pos(substr, HTML) - 1, Length(HTML) - Pos(substr, HTML));
 Result := HTML;
end;

function parseHTMLBefore(html: string; substr: string): string;
begin
 Delete(HTML, 1, Pos(substr ,html) - 1);
 Result := HTML;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
 HTML: string;
begin
 HTML := '<h1 class="tt">example</h1></div><div class="bl_la_main"><div class="divtext">';
 ShowMessage(parseHTMLBefore(HTML, '<div class="bl_la_main">'));
end;

Result:

 <div class="bl_la_main"><div class="divtext">