如何在Delphi中转换HTML webform的参数以与TIdHTTP一起使用？

<form action="/submit" method="post">
  <input type="text" name="username" value="JohnDoe">
  <input type="password" name="password" value="secret">
  <input type="submit" value="Submit">
</form>

uses
  IdHTTP, SysUtils;

var
  formData: TStringList;
begin
  formData := TStringList.Create;
  try
    formData.Add('username=JohnDoe');
    formData.Add('password=secret');

    // 继续处理发送请求的代码
  finally
    formData.Free;
  end;
end;

uses
  IdHTTP, IdGlobal;

var
  idHttp: TIdHTTP;
  response: String;
begin
  idHttp := TIdHTTP.Create(nil);
  try
    response := idHttp.Post('http://example.com/submit', formData);
    // 处理响应
  finally
    idHttp.Free;
  end;
end;

uses
  IdURI;

var
  encodedData: TStringList;
begin
  encodedData := TStringList.Create;
  try
    encodedData.Add(IdURI.URLEncode('username=JohnDoe'));
    encodedData.Add(IdURI.URLEncode('password=secret'));

    response := idHttp.Post('http://example.com/submit', encodedData);
  finally
    encodedData.Free;
  end;
end;

idHttp.ReadTimeout := 5000; // 5秒
idHttp.ConnectTimeout := 5000; // 5秒