Format exception was unhandled in c# windows application overcome this

S J

5y877Visual Basic .NET

when i am click button validating empty textboxes it showing exception

"Input string was not in a correct format."

how to resolve this

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sachin Singh5y ago
Accepted answer
As per Your code , everything is fine.
There is no chance of error untill from textboxes you paas other types than int or is empty.
if you are passing string from Textbox then error will come
If you are not paasing anything then error will come

Do it like below
public void Validations()
{
if(string.IsNullOrEmpty(txtX.Text)||string.IsNullOrEmpty(txtY.Text)||string.IsNullOrEmpty(txtWidth.Text)||string.IsNullOrEmpty(txtHeight.Text))
{
MessageBox.Show("Please fill all the feilds ");
}
else
{
x = Convert.ToInt32(txtX.Text);
y = Convert.ToInt32(txtY.Text);
h = Convert.ToInt32(txtHeight.Text);
w = Convert.ToInt32(txtWidth.Text);
}
}

public void createRectangle()
{

rectangle1 = new Rectangle(x, y, w, h);
}
Sachin Singh5y ago
Please put your validation Code,
BTW Input string was not in a correct format means you are trying to convert string into some other dataType but the string is either Null or compilar have no way to convert that string into the dataType you are trying to convert to.
Rajanikant Hawaldar5y ago
Hello Shilpa, Please refer below sample code to know how to convert textbox string to other type, here converting textbox string to float.
private void button1_Click(object sender, EventArgs e)
       {

           textBox2.Text = "0.5";
           if (!string.IsNullOrWhiteSpace(textBox2.Text))
           {
               float _value;
               if (Single.TryParse(textBox2.Text.Trim().ToString(), out _value))
               {
                   //success code
                   Console.WriteLine("textbox contains proper value");
               }
               else
               {
                   //failure code
                   Console.WriteLine("textbox does not contains proper value");
               }
           }
       }
Amit Gupta5y ago
Show us the validation code. For checking empty fields you can use string.IsNullOrEmpty(rxtbox1.text)