Format exception was unhandled in c# windows application overcome this

Question

when i am click button validating empty textboxes it showing exception "Input string was not in a correct format." how to resolve this

Sachin Singh · 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 Singh · Answer

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.

Amit Gupta · Answer

Show us the validation code. For checking empty fields you can use string.IsNullOrEmpty(rxtbox1.text)

Rajanikant Hawaldar · Answer

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" ); } } }

Format exception was unhandled in c# windows application overcome this

Answers (4)