Math Functions

 String to Floating-Point Conversion

To convert the value of a string to floating number, use the AnsiString::ToDouble() method. Its syntax is:

`double __fastcall ToDouble() const;`

Here is an example:

```//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
double Value1 = Edit1->Text.ToDouble();
double Value2 = Edit2->Text.ToDouble();

double Value3 = Value1 + Value2;
Edit3->Text = Value3;
}
//---------------------------------------------------------------------------```

Another function used to convert a string to a floating-point value is the StrToFloat() function whose syntax is:

`Extended __fastcall StrToFloat(const AnsiString S);`

This function takes one argument, which is the string to convert. The function returns a long double-precision value. Here is an example:

```//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
double Value1 = StrToFloat(Edit1->Text);
double Value2 = StrToFloat(Edit2->Text);

double Value3 = Value1 + Value2;
Edit3->Text = Value3;
}
//---------------------------------------------------------------------------```