how to convert empty string to int

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Hi all,

I have two textboxes.

how to convert empty string to int
my code like this.

textbox1.Text="";

int a= convert.ToInt32(textbox1.Text);
i got the error

Input string was not in a correct format.
int a = Convert.ToInt32(textbox1.Text);

Posted 7-Feb-13 2:19am

Santhosh23

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3 solutions

Solution 5

Another solution for this is to just have a check and see if your textbox is empty:

C#

if(textBox1.Text.Equals(""))
{
    int a = 0;
}

Also later on you have to use regular expressions to check if the input box contains anything other than numbers. If it doesn't then convert it to integer straight away, otherwise display an error.

Posted 7-Feb-13 3:20am

shiny13

Solution 2

hi all,

C#

int? lat1 = string.IsNullOrEmpty(txtempid.Text) ? (int?)null : Convert.ToInt32(txtempid.Text);
          int empid = Convert.ToInt32(lat1);

this code working fine

Posted 7-Feb-13 2:49am

Santhosh23

Comments

Pete O'Hanlon 7-Feb-13 8:53am

Wow. There's so much wrong with this solution I don't know where to start. Ok, first of all, don't use Convert.ToInt32 - what happens if the user has typed 1.2 in the text box? Secondly, why cast to (int?) null when you could just have put 0 in there and removed the nullable int? Finally - and most importantly, TryParse sets the output to 0 if it's an invalid value in there.

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Ankur^\m/ · Accepted Answer · 2013-02-07T02:27:00

Solution 1

Use Int32.TryParse Method[^]

C#

bool success = Int32.TryParse(textbox1.Text, out a);

a will contain 0, if the conversion was unsuccessful.

Posted 7-Feb-13 2:27am

Ankur^\m/

Comments

Kishor Deshpande 7-Feb-13 8:39am

My 5

Ankur^\m/ 7-Feb-13 9:10am

Thanks you!

Zoltán Zörgő 7-Feb-13 8:52am

That's the way, +5!

Ankur^\m/ 7-Feb-13 9:06am

Thanks for the vote!

manognya kota 7-Feb-13 9:16am

+5'ed !