The original website of this article is: http://bbs.bccn.net/thread-205138-1-1.html
private void tBox_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == 0x20) e.KeyChar = (char)0; //Disable the space key
if ((e.KeyChar == 0x2D) && (((TextBox) sender).Text.Length == 0)) return; //Handle negative numbers
if (e.KeyChar> 0x20)
{
try
{
double.Parse(((TextBox)sender).Text + e.KeyChar.ToString());
}
catch
{
e.KeyChar = (char)0; //Handle illegal characters
}
}
} private void TextBox_KeyPress(object sender, KeyPressEventArgs e) {
if(e.KeyChar!=8&&!Char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
}
or private void TextBox_KeyPress(object sender, KeyPressEventArgs e)
{
if(e.KeyChar!='\b' &&!Char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
} private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e) { if(e.KeyChar!='\b')/ /This is to allow the input of the backspace key { if((e.KeyChar<'0')||(e.KeyChar>'9'))//This is to allow the input of 0-9 numbers { e.Handled = true; } } } private void button1_Click(object sender, EventArgs e) {
string text = this.textBox1.Text;
if (text != null)
MessageBox.Show(text);
}
private void textBox1_Validating(object sender, CancelEventArgs e)
{
const string pattern = @"^\d+\.?\d+$";
string content = ((TextBox)sender).Text;
if (!(Regex.IsMatch(content, pattern)))
{
errorProvider1.SetError((Control)sender, "只能输入数字!");
e.Cancel = true;
}
else
errorProvider1.SetError((Control)sender, null);
}
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if(e.KeyChar=='.' && this.textBox1.Text.IndexOf(".")!=-1)
{
e.Handled=true;
}
if(!((e.KeyChar>=48 && e.KeyChar<=57) || e.KeyChar=='.' || e.KeyChar==8))
{
e.Handled=true;
}
}
private void tbx_LsRegCapital_KeyPress(object sender, KeyPressEventArgs e)
{
if (!Char.IsNumber(e.KeyChar) && !Char.IsPunctuation(e.KeyChar) && !Char.IsControl(e.KeyChar))
{
e.Handled = true;//消除不合适字符
}
else if (Char.IsPunctuation(e.KeyChar))
{
if (e.KeyChar != '.' || this.textBox1.Text.Length == 0)//小数点
{
e.Handled = true;
}
if (textBox1.Text.LastIndexOf('.') != -1)
{
e.Handled = true;
}
}
}