我在CodePlex上做了一些东西。

它通过拦截TextChanged事件来工作。如果结果是一个好的数字，它将被存储。如果是错误的，最后的好值将恢复。源代码有点太大，不适合在这里发布，但这里有一个指向处理此逻辑核心的类的链接。

Here is a simple solution that works for me.

public static bool numResult;
    public static bool checkTextisNumber(string numberVal)
    {
        try
        {
            if (numberVal.Equals("."))
            {
                numResult = true;
            }
            else if (numberVal.Equals(""))
            {
                numResult = true;
            }
            else
            {
                decimal number3 = 0;
                bool canConvert = decimal.TryParse(numberVal, out number3);
                if (canConvert == true)
                {
                    numResult = true;
                }
                else
                    numResult = false;
            }

        }
        catch (System.Exception ex)
        {
            numResult = false;
        }
        return numResult;
    }
    string correctNum;
    private void tBox_NumTester_TextChanged(object sender, TextChangedEventArgs e)
    {


        if(checkTextisNumber(tBox_NumTester.Text))
        {
            correctNum = tBox_NumTester.Text;
        }
        else
        {
            tBox_NumTester.Text = correctNum;
        }

    }

3解决方案

1)

//Add to the textbox's KeyPress event
//using Regex for number only textBox

private void txtBox_KeyPress(object sender, KeyPressEventArgs e)
{
if (!System.Text.RegularExpressions.Regex.IsMatch(e.KeyChar.ToString(), "\\d+"))
e.Handled = true;
}

2） 来自MSDN的另一个解决方案

// 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, 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;
        }
    }
}

}

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (nonNumberEntered == true)
    {
       MessageBox.Show("Please enter number only..."); 
       e.Handled = true;
    }
}

源http://msdn.microsoft.com/en-us/library/system.windows.forms.control.keypress (v =应用程序). aspx

3)使用MaskedTextBox: http://msdn.microsoft.com/en-us/library/system.windows.forms.maskedtextbox.aspx

整数和浮点数都需要被接受，包括负数。

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    // Text
    string text = ((Control) sender).Text;

    // Is Negative Number?
    if (e.KeyChar == '-' && text.Length == 0)
    {
        e.Handled = false;
        return;
    }

    // Is Float Number?
    if (e.KeyChar == '.' && text.Length > 0 && !text.Contains("."))
    {
        e.Handled = false;
        return;
    }

    // Is Digit?
    e.Handled = (!char.IsDigit(e.KeyChar) && !char.IsControl(e.KeyChar));
}

故障安全和简单的“递归”方法，可用于多个文本框。

它可以阻止错误的键盘输入字符，也可以粘贴值等。它只接受整数，最大数字长度是字符串类型的最大长度(它是int，真的很长!)

public void Check_If_Int_On_TextChanged(object sender, EventArgs e)
{
   // This method checks that each inputed character is a number. Any non-numeric
   // characters are removed from the text

   TextBox textbox = (TextBox)sender;

   // If the text is empty, return
   if (textbox.Text.Length == 0) { return; }

   // Check the new Text value if it's only numbers
   byte parsedValue;
   if (!byte.TryParse(textbox.Text[(textbox.Text.Length - 1)].ToString(), out parsedValue))
   {
      // Remove the last character as it wasn't a number
      textbox.Text = textbox.Text.Remove((textbox.Text.Length - 1));

      // Move the cursor to the end of text
      textbox.SelectionStart = textbox.Text.Length;
    }
 }

我一直致力于一个组件的集合来完成WinForms中缺失的东西，这里是:高级表单

特别地，这是一个正则文本框类

/// <summary>Represents a Windows text box control that only allows input that matches a regular expression.</summary>
public class RegexTextBox : TextBox
{
    [NonSerialized]
    string lastText;

    /// <summary>A regular expression governing the input allowed in this text field.</summary>
    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
    public virtual Regex Regex { get; set; }

    /// <summary>A regular expression governing the input allowed in this text field.</summary>
    [DefaultValue(null)]
    [Category("Behavior")]
    [Description("Sets the regular expression governing the input allowed for this control.")]
    public virtual string RegexString {
        get {
            return Regex == null ? string.Empty : Regex.ToString();
        }
        set {
            if (string.IsNullOrEmpty(value))
                Regex = null;
            else
                Regex = new Regex(value);
        }
    }

    protected override void OnTextChanged(EventArgs e) {
        if (Regex != null && !Regex.IsMatch(Text)) {
            int pos = SelectionStart - Text.Length + (lastText ?? string.Empty).Length;
            Text = lastText;
            SelectionStart = Math.Max(0, pos);
        }

        lastText = Text;

        base.OnTextChanged(e);
    }
}

简单地添加像myNumbericTextBox这样的东西。RegexString = "^(\\d+|)$";应该足够了。