third form

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.Menus;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Edit2: TEdit;
    Label3: TLabel;
    Label4: TLabel;
    Edit1: TEdit;
    Button1: TButton;
    Label7: TLabel;
    Label8: TLabel;
    MainMenu1: TMainMenu;
    PopupMenu1: TPopupMenu;
    N1: TMenuItem;
    N2: TMenuItem;
    N3: TMenuItem;
    N4: TMenuItem;
    N5: TMenuItem;
    OpenDialog1: TOpenDialog;
    SaveDialog1: TSaveDialog;
    procedure Edit1Change(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Edit1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit2KeyPress(Sender: TObject; var Key: Char);
    procedure N4Click(Sender: TObject);
    procedure N5Click(Sender: TObject);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure N2Click(Sender: TObject);
    procedure N3Click(Sender: TObject);
    procedure Edit2Change(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  Path, Result : String;
  IsFileOpen, Flag : Boolean;

implementation

{$R *.dfm}



procedure TForm1.Button1Click(Sender: TObject);
var
    N : Integer;
    Eps, X, Y0, Y: Real;
begin
    Try
        X := StrToFloat(Edit1.Text);
    Except
        Application.MessageBox('Что-то не так', 'Ашыпка', 0);
        Edit1.Text := '';
    End;
    Try
        Eps := StrToFloat(Edit2.Text);
    Except
        Application.MessageBox('Что-то не так', 'Ашыпка', 0);
        Edit2.Text := '';
    End;
    Y0 := 1;
    N := 0;
    Repeat
        Y := Y0;
        Y0 := 0.5 * (Y + X / Y);
        Inc(N);
    Until (abs(Y - Y0) <= Eps);
    Label7.Caption := (FormatFloat('0.00000000',Y0));
    Label8.Caption := IntToStr(N);
    N3.Enabled := True;
    Result := 'Y = ' + Label7.Caption + ' and ' +'N = ' + Label8.Caption;
end;

procedure TForm1.Edit1Change(Sender: TObject);
begin
    N3.Enabled := False;
    If (Length(Edit1.Text) = 0) or (Length(Edit2.Text) = 0) then
        Button1.Enabled := False
    else
        Button1.Enabled := True;
    Label7.Caption := '';
    Label8.Caption := '';
end;

procedure TForm1.Edit2Change(Sender: TObject);
begin
    If (Length(Edit1.Text) = 0) or (Length(Edit2.Text) = 0) then
        Button1.Enabled := False
    else
        Button1.Enabled := True;
    If (Length(Edit2.Text) <> 0) then
        If (StrToFloat(Edit2.Text) = 0) or (Edit2.Text = '0,') or (Length(Edit1.Text) = 0) then
            Button1.Enabled := False
        else
            Button1.Enabled := True;
    Label7.Caption := '';
    Label8.Caption := '';

end;

procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
var
    N : Integer;
begin
    If ((Key = #13) And (Button1.Enabled)) Then
        Button1.Click;
    If (Not(Key In ['0'..'9', #08, #46,','])) Then
        Key := #0;
    If (Length(Edit1.Text) = 8) Then
        If (Not(Key In [#08, #46])) Then
            Key := #0;
    if (Length(Edit1.Text) = 0) then
        If (Not(Key In ['0'..'9', #08, #46])) Then
            Key := #0;
    N := Ansipos(',', Edit1.Text);
    If (Key = ',') and (N <> 0) then
        If (Not(Key In ['0'..'9', #08, #46])) Then
            Key := #0;
    If (Edit1.Text = '0') and Not(Key in [',', #08, #46]) then
        Key := #0;
    If Key = '.' then
        Key := #0;
end;

procedure TForm1.Edit2KeyPress(Sender: TObject; var Key: Char);
var
    N : Integer;
begin
    If ((Key = #13) And (Button1.Enabled)) Then
        Button1.Click;
    If (Not(Key In ['0'..'9', #08, #46, ','])) Then
        Key := #0;
    If (Length(Edit2.Text) = 8) Then
        If (Not(Key In [#08, #46])) Then
            Key := #0;
    if (Length(Edit2.Text) = 0) then
        If (Not(Key In ['0'..'9', #08, #46])) Then
            Key := #0;
    N := Ansipos(',', Edit2.Text);
    If (Key = ',') and (n <> 0) then
        If (Not(Key In ['0'..'9', #08, #46])) Then
            Key := #0;
    If (Edit2.Text = '0') and Not(Key in [',', #08, #46]) then
        Key := #0;
    If Key = '.' then
        Key := #0;
end;

procedure TForm1.N4Click(Sender: TObject);
begin
      Application.MessageBox('Программа вычисляет значение квадратного корня с точностью, вводимой пользователем. Также подсчитывает количество итераций, за которое достигается эта точность.', 'Инструкция', 0);
end;

procedure TForm1.N5Click(Sender: TObject);
begin
     Application.MessageBox('Арефин Владислав гр.251004', 'Разрабочик', 0);
end;

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
    CanClose := MessageBox(Form1.Handle, 'Вы уверены, что хотите выйти?', 'Выход', MB_YESNO + MB_ICONQUESTION)=ID_YES;
end;




Function CheckFileData1(Num: String): Boolean;
Const
    MAX_LIM = 99999999;
    MIN_LIM = 0;
Var
    NewNum: Real;
    IsCorrect: Boolean;
Begin
    NewNum := 0;
    IsCorrect := True;
    Try
        NewNum := StrToFloat(Num);
    Except
        MessageBox(Form1.Handle, Pchar('Проверьте корректность данных.'), 'Ошибка', MB_ICONSTOP);
        IsCorrect := False;
    End;
    If(IsCorrect And ((NewNum > MAX_LIM) Or (NewNum < MIN_LIM))) Then
    Begin
        Num := FloatToStr(NewNum);
        MessageBox(Form1.Handle, Pchar('Недопустимое значение!'), 'Ошибка', MB_ICONSTOP);
        IsCorrect := False;
    End;
    CheckFileData1 := IsCorrect;
End;

Function CheckFileData2(Num: String): Boolean;
Const
    MAX_LIM = 99999999;
    MIN_LIM = 0;
Var
    NewNum: Real;
    IsCorrect: Boolean;
Begin
    NewNum := 0;
    IsCorrect := True;
    Try
        NewNum := StrToFloat(Num);
    Except
        MessageBox(Form1.Handle, Pchar('Проверьте корректность данных.'), 'Ошибка', MB_ICONSTOP);
        IsCorrect := False;
    End;
    If(IsCorrect And ((NewNum > MAX_LIM) Or (NewNum <= MIN_LIM))) Then
    Begin
        Num := FloatToStr(NewNum);
        MessageBox(Form1.Handle, Pchar('Недопустимое значение!'), 'Ошибка', MB_ICONSTOP);
        IsCorrect := False;
    End;
    CheckFileData2 := IsCorrect;
End;


Function Open (): String;
Begin
    With Form1 Do
    Begin
        If OpenDialog1.Execute Then
        Begin
            Path := OpenDialog1.FileName;
            IsFileOpen := True;
        End
        Else
            IsFileOpen := False;
    End;
    Open := Path;
End;

Function TakeDataFromFile1(Number1: String; Var FileOutput: TextFile): String;
Var
    IsRight: Boolean;
Begin
    IsRight := True;
    Try
        Readln(FileOutput, Number1);
        IsRight := CheckFileData1(Number1);
    Except
    End;
    If(Not(IsRight)) Then
        TakeDataFromFile1 := ''
    Else
        TakeDataFromFile1 := Number1;
End;

Function TakeDataFromFile2(Number2: String; Var FileOutput: TextFile): String;
Var
    IsRight : Boolean;
Begin
    IsRight := True;
    Try
        Read(FileOutput, Number2);
        IsRight := CheckFileData2(Number2);
    Except
    End;
    If(Not(IsRight)) Then
        TakeDataFromFile2 := ''
    Else
        TakeDataFromFile2 := Number2;
End;


procedure TForm1.N2Click(Sender: TObject);
Var
    FileInput: TextFile;
    Num : Integer;
    Str1, Str2 : String;
begin
    Num := 0;
    Path := Open;
    AssignFile(FileInput, Path);
    Reset(FileInput);
    If(IsFileOpen) Then
    Begin
        Str1 := TakeDataFromFile1(IntToStr(Num), FileInput);
        if Str1 <> '' then
            Str2 := TakeDataFromFile2(IntToStr(Num), FileInput);
    End;
    if Not((Str1 = '') or (Str2 = '')) then
    Begin
        Edit1.Text := Str1;
        Edit2.Text := Str2;
    End
    Else
    Begin
        Edit1.Text := #0;
        Edit2.Text := #0;
    End;
    CloseFile(FileInput);
end;

procedure TForm1.N3Click(Sender: TObject);
Var
    FileOutput: TextFile;
begin
    Path := Open;
    If (IsFileOpen) Then
    Begin
        AssignFile(FileOutput, Path);
        Rewrite(FileOutput);
        Write(FileOutput, Result);
        Application.MessageBox('Запись файла выполнена успешно.', 'Результат', 0);
        CloseFile(FileOutput);
        Label7.Caption := '';
        Label8.Caption := '';
        Edit1.Text := '';
        Edit2.Text := '';
    End;
end;

end.