How can I convert String to Int?

Question

I have a TextBoxD1.Text and I want to convert it to an int to store it in a database.

How can I do this?

Answer 1

You can use either,

int i = Convert.ToInt32(TextBoxD1.Text);

or

int i =int.Parse(TextBoxD1.Text);

Answer 2

You need to parse the string, and you also need to ensure that it is truly in the format of an integer.

The easiest way is this:

int parsedInt = 0;
if (int.TryParse(TextBoxD1.Text, out parsedInt))
{
   // Code for if the string was valid
}
else
{
   // Code for if the string was invalid
}

Answer 3

As explained in the TryParse documentation, TryParse() returns a boolean which indicates that a valid number was found:

bool success = Int32.TryParse(TextBoxD1.Text, out val);

if (success)
{
// put val in database
}
else
{
// handle the case that the string doesn't contain a valid number
}

Answer 4

Be carefull when using Convert.ToInt32() on a char!
It will return the UTF-16 Code of the character!

If you access the string only in a certain position using the [i] indexing operator it will return a char and not a string!

String input = "123678";

int x = Convert.ToInt32(input[4]);  // returns 55

int x = Convert.ToInt32(input[4].toString());  // returns 7

Answer 5

Enjoy it...

int i = 0;
string s = "123";
i =int.Parse(s);
i = Convert.ToInt32(s);

Answer 6

int.TryParse()

It won't throw if the text is not numeric.