我有,我想只有在接受字母值的maskedtextbox
控制Windows窗体应用程序。如何使文本框只接受字母字符
理想的情况下,这会表现得这样按其它键比字母键会要么不产生任何结果,要么立即向用户提供关于无效字符的反馈。
我有,我想只有在接受字母值的maskedtextbox
控制Windows窗体应用程序。如何使文本框只接受字母字符
理想的情况下,这会表现得这样按其它键比字母键会要么不产生任何结果,要么立即向用户提供关于无效字符的反馈。
从MSDN(这段代码展示了如何处理KeyDown事件来检查输入的字符,在这个例子中它只检查数字输入,你可以修改它,以便它可以用于字母输入,而不是数值):
// Boolean flag used to determine when a character other than a number is entered.
private bool nonNumberEntered = false;
// Handle the KeyDown event to determine the type of character entered into the control.
private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
// Initialize the flag to false.
nonNumberEntered = false;
// Determine whether the keystroke is a number from the top of the keyboard.
if (e.KeyCode < Keys.D0 || e.KeyCode > Keys.D9)
{
// Determine whether the keystroke is a number from the keypad.
if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)
{
// Determine whether the keystroke is a backspace.
if(e.KeyCode != Keys.Back)
{
// A non-numerical keystroke was pressed.
// Set the flag to true and evaluate in KeyPress event.
nonNumberEntered = true;
}
}
}
//If shift key was pressed, it's not a number.
if (Control.ModifierKeys == Keys.Shift) {
nonNumberEntered = true;
}
}
// This event occurs after the KeyDown event and can be used to prevent
// characters from entering the control.
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
// Check for the flag being set in the KeyDown event.
if (nonNumberEntered == true)
{
// Stop the character from being entered into the control since it is non-numerical.
e.Handled = true;
}
}
此代码将区分字母按键从非字母的:
private void maskedTextBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (Regex.IsMatch(e.KeyChar.ToString(), @"\p{L}"))
{
// this is a letter
}
else
{
// this is NOT a letter
}
}
更新:请注意,上述正则表达式将只匹配字母字符,所以它不会允许SPAC es,逗号,点等。为了让更多类型的字符,你需要将这些添加到模式:
// allow alphabetic characters, dots, commas, semicolon, colon
// and whitespace characters
if (Regex.IsMatch(e.KeyChar.ToString(), @"[\p{L}\.,;:\s]"))
这个问题可能已经问及对每一个可以想象的编程论坛回答了百万次。所提供的每一个答案都有一个独特于所述要求的区别。
由于您使用的是MaskedTextBox
,因此您可以使用其他验证功能,并且不需要处理按键。您可以简单地将Mask属性设置为“L”(需要输入字符)或“?” (可选字符)。为了向用户显示输入不可接受的反馈,可以使用BeepOnError
属性或添加工具提示来显示错误消息。这个反馈机制应该在MaskedInputRejected
事件处理程序中执行。
MaskedTextBox
控件提供ValidatingType
属性来检查通过掩码要求的输入,但可能不是正确的数据类型。在此类型验证之后引发TypeValidationCompleted
事件,您可以处理它以确定结果。
如果您仍然需要处理按键事件,请继续阅读...!
我推荐你的方法是,不是处理KeyDown
事件(你表面上不需要高级密钥处理能力),或者使用正则表达式来匹配输入(坦率地说,过度杀伤),我会简单地使用内置的-in属性的Char结构。
private void maskedTextBox1_KeyPress(object sender, KeyPressEventArgs e)
{
Char pressedKey = e.KeyChar;
if (Char.IsLetter(pressedKey) || Char.IsSeparator(pressedKey) || Char.IsPunctuation(pressedKey))
{
// Allow input.
e.Handled = false
}
else
// Stop the character from being entered into the control since not a letter, nor punctuation, nor a space.
e.Handled = true;
}
}
请注意,此代码段允许您处理punctutation和分隔符键。
// This is to allow only numbers.
// This Event Trigger, When key press event occures ,and it only allows the Number and Controls.,
private void txtEmpExp_KeyPress(object sender, KeyPressEventArgs e)
{
if(Char.IsControl(e.KeyChar)!=true&&Char.IsNumber(e.KeyChar)==false)
{
e.Handled = true;
}
}
//At key press event it will allows only the Characters and Controls.
private void txtEmpLocation_KeyPress(object sender, KeyPressEventArgs e)
{
if (Char.IsControl(e.KeyChar) != true && Char.IsNumber(e.KeyChar) == true)
{
e.Handled = true;
}
}
//添加一个文本框选择它&转到活动&在的“按键”事件的事件列表中双击。
if (!char.IsLetter(e.KeyChar))
{
MessageBox.Show("Enter only characters");
}
}
这对我的作品:)
private void txt_KeyPress(object sender, KeyPressEventArgs e)
{
e.Handled = !((e.KeyChar != 'ñ' && e.KeyChar != 'Ñ') && char.IsLetter(e.KeyChar));
}
尝试this代码
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
e.Handled = !(char.IsLetter(e.KeyChar) || e.KeyChar == (char)Keys.Back || e.KeyChar == (char)Keys.Space);
}
可能要修复您的格式。 – 2011-07-11 17:34:30