Continue Adding Value from TextBox

Question

Please Guys

 

I want to add every value i enter in a textbox continuously. But i always get result once.

 

say i enter :

 

10+10=20

20+30=50

50+5=55.....

 

With every value i enter in the textbox adding to the result.

 

In fact it work well in windows Forms but not working well in mvc and web forms.

 

See the code Below

int Total = 0;
int Adxer;
protected void Button1_Click(object sender, EventArgs e)
{
int Amount = Convert.ToInt32(TextBox1.Text);
Adxer = Total - Amount;
Total = Adxer;
Label1.Text = Total.ToString();
}
MVC Code
public ActionResult OscarProRe( int Amount=0)
{
if(btn != null)
{
int addy = Amount;
int Total;
Total = userB + addy;
userB = Total;
ViewBag.To = userB;
}
}

Please in mvc the value does not add to the result.

 

Help me find out where i got it wrong

 

Any answer is Warmly welcome. Thanks