Validating TextBox in Form

Preeti Agrawalla

13y1.8kLearn iOS Programming

I am validating textbox1 of below attached project, but i am getting error. Please check it.

16 Replies

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Iftikar Hussain13y ago
Accepted answer
I have modified your code. Please check

Regards,
Iftikar
Iftikar Hussain13y ago
in that case you can use MaskedTextBox. Please refer the below link

http://www.c-sharpcorner.com/uploadfile/mahesh/maskedtextbox-in-C-Sharp/

Regards,
Iftikar
Preeti Agrawalla13y ago
Hey iftikar, thanks ur code is working. If i want that textbox will enter only phone numbers, like it will allow only 10 digit numbers, not less than that and not more than that, then what i have to do???
Preeti Agrawalla13y ago
IT'S Working, but when i press "backspace" key, it also shows error. I want that it will also allow "backspace" key.
Satyapriya Nayak13y ago
private void textBox1_KeyPress(object sender, KeyPressEventArgs e) { if (!System.Text.RegularExpressions.Regex.IsMatch(e.KeyChar.ToString(), "\\d+")) { e.Handled = true; MessageBox.Show("error"); } }
Preeti Agrawalla13y ago
Iftikar, Anurag, I m trying to do this, but not getting exact result, plz check my code.
Anurag Sarkar13y ago
private void textBox3_KeyPress(object sender, KeyPressEventArgs e)
{
if (char.IsDigit(e.KeyChar) || char.IsControl(e.KeyChar))
{
e.Handled = false;
}
else
{
e.Handled = true;
}
}

You should try to this code.
Iftikar Hussain13y ago
Hi,
Try like this

this.textBox1.KeyPress += new KeyPressEventHandler(this.textBox1_KeyPress);

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) && e.KeyChar == '.')
{
e.Handled = true;
}
}

Regards,
Iftikar
Preeti Agrawalla13y ago
Anurag, I want that these two textbox will only allow integer numbers not alphabets, for that what i have to do?
Anurag Sarkar13y ago
I am provinding you the sample have a look at it.

private void button2_Click(object sender, EventArgs e)
{
if (textBox3.Text == "")
{
this.errorProvider1.SetError(textBox3, "This Cannott be Blank");
return;
}
if (textBox4.Text == "")
{
this.errorProvider1.SetError(textBox4, "This Cannott be Blank");
return;
}
int s1, s2, s3;
string s;
s1 = Convert.ToInt32(textBox3.Text);
s2 = Convert.ToInt32(textBox4.Text);
s3 = s1 + s2;
s = Convert.ToString(s3);
frmTest2 myObjViewer = new frmTest2();
// hiding the first form.
this.Hide();
myObjViewer.Controls["label2"].Text = s;
// displaying the second form
myObjViewer.ShowDialog();

}
Just run the application you will get the result.
While you will be creating new project you need to drag a error provide control from the toolbox.
Have a look at the sample.
Preeti Agrawalla13y ago
Yes Anurag
Anurag Sarkar13y ago
Do you want to use Error Provide Validation ?
Anurag Sarkar13y ago
I have just put a simple blank validation you can use what ever you want to.
Preeti Agrawalla13y ago
Anurag, I want to use validation control. so please help me by using Validator. Thanks
Preeti Agrawalla13y ago
I have already attached my project by following this link
http://www.codeproject.com/Articles/13922/Validate-user-input-in-Windows-Forms

But i m getting error.
Anurag Sarkar13y ago
private void button1_Click(object sender, EventArgs e)
        {
if(textBox1.text=""){MessageBox.Show("Enter Number");return;}
if(textBox2.text=""){MessageBox.Show("Enter Second Number");return;}
            int s1, s2, s3;
            string s;
            s1 = Convert.ToInt32(textBox1.Text);
            s2 = Convert.ToInt32(textBox2.Text);
            s3 = s1 + s2;
            s = Convert.ToString(s3);
            frmTest2 myObjViewer = new frmTest2();
            // hiding the first form.
            this.Hide();
            myObjViewer.Controls["label2"].Text = s;
            // displaying the second form
            myObjViewer.ShowDialog();

        }

Just Put this Code in your form 1.