winform文本框，如何只允许输入数字和小数点？

[menganafff]

多谢！

[applethink]

在keydown 事件里判断键入的值就行了

[manonroad]

重写OnKeysDown或者OnKeysUp

[lovexin]

欢望中呀．．

[lalac]

1、改用MaskedTextBox，然后设置Mask即可。这里有一个示例：

下面的代码示例初始化 MaskedTextBox 以接受日期，并且将使用 MaskInputRejected 和 TypeValidationCompleted 事件来警告用户输入了无效值。

private void Form1_Load(object sender, EventArgs e)
{
    maskedTextBox1.Mask = "00/00/0000";

    maskedTextBox1.MaskInputRejected += new MaskInputRejectedEventHandler(maskedTextBox1_MaskInputRejected);
    maskedTextBox1.KeyDown += new KeyEventHandler(maskedTextBox1_KeyDown);
}

void maskedTextBox1_MaskInputRejected(object sender, MaskInputRejectedEventArgs e)
{
    if (maskedTextBox1.MaskFull)
    {
        toolTip1.ToolTipTitle = "Input Rejected - Too Much Data";
        toolTip1.Show("You cannot enter any more data into the date field. Delete some characters in order to insert more data.", maskedTextBox1, maskedTextBox1.Location.X, maskedTextBox1.Location.Y, 5000);
    }
    else if (e.Position == maskedTextBox1.Mask.Length)
    {
        toolTip1.ToolTipTitle = "Input Rejected - End of Field";
        toolTip1.Show("You cannot add extra characters to the end of this date field.", maskedTextBox1, maskedTextBox1.Location.X, maskedTextBox1.Location.Y, 5000);
    }
    else
    {
        toolTip1.ToolTipTitle = "Input Rejected";
        toolTip1.Show("You can only add numeric characters (0-9) into this date field.", maskedTextBox1, maskedTextBox1.Location.X, maskedTextBox1.Location.Y, 5000);
    }
}

void maskedTextBox1_KeyDown(object sender, KeyEventArgs e)
{
    // The balloon tip is visible for five seconds; if the user types any data before it disappears, collapse it ourselves.
    toolTip1.Hide(maskedTextBox1);
}

2、在KeyPress中处理键入的值，并把e.Handle设置为true表示处理了。

[jimgreat]

这是个继承TextBox写成的只接收数字的TextBox

using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Windows.Forms.Design;

namespace CustomControls
{
    /// <summary>
    /// NumbersOnlyTextBox class
    /// </summary>
    [Designer(typeof(NumbersOnlyTextBox.NumbersOnlyTextBoxDesigner))]
    public class NumbersOnlyTextBox:System.Windows.Forms.TextBox
    {
        [DllImport("user32.dll")]
        private static extern bool MessageBeep(uint uType);

        public override bool PreProcessMessage(ref Message msg)
        {
            int keyValue = msg.WParam.ToInt32();
            if ((keyValue > 47 && keyValue < 58) || keyValue == 46 || (keyValue > 34 && keyValue < 41) || keyValue == 8)
            {
                return base.PreProcessMessage(ref msg);
            }
            else
            {
                //Delete Key
                if (msg.Msg == 256 && keyValue == 46)
                {
                    return base.PreProcessMessage(ref msg);
                }
                //Windows message id used to limit 1 beep per keystroke
                if (msg.Msg == 258)
                {
                    MessageBeep(0);
                }

                return true;

            }

        }

        public NumbersOnlyTextBox()
        {
 

        }


        #region Internal Classes
        /// <summary>
        /// 
        /// </summary>
        internal class NumbersOnlyTextBoxDesigner : System.Windows.Forms.Design.ControlDesigner
        {
        #region Method Overrides
        protected override void PostFilterProperties(System.Collections.IDictionary properties)
        {
            //base.PostFilterProperties(properties);
            properties.Remove("Text");
        }
        #endregion
        }

        #endregion

    }

   

}

[menganafff]

我用的是2003，找不到MaskedTextBox

只接受数字不行，我还要输入小数点啊

[peterb]

在onchange事件用正则表达式验证也可以

[Sali]

在要求输入数字的控件的KeyPress事件下判断输入的字符的ASCII编码值（0的ASCII编码值是48，9的ASCII编码值是57，小数点的ASCII编码值是46），如果输入的符合要求则不作处理，如果不符合要求，则添加代码：e.Handle=true

[benniaoyaofei]

^[-]?\d+[.]?\d*$

[ydfy6]

用正则表达式可以

[ydfy6]

或者用ASCII判断

[menganafff]

用ASCII编码值来判断，英文虽然不能输入了，但中文还是能输入的

[myhomeland]

用正则表达式吧,用KeyPress事件下判断输入的字符的ASCII编码值有一定的局限,比如说对两个小数点及以上的还要单独判断,其实用现成的numericUpDown就可以了