Winform TextBox中只能输入数字的几种常用方法(C#)

private void tBox_KeyPress(object sender, KeyPressEventArgs e)

       
{

            if (e.KeyChar == 0x20) e.KeyChar = (char)0;  //禁止空格键

           
if ((e.KeyChar == 0x2D) && (((TextBox)sender).Text.Length ==
0)) return;   //处理负数

            if (e.KeyChar > 0x20)

           
{

                try

                {

                   
double.Parse(((TextBox)sender).Text + e.KeyChar.ToString());

               
}

                catch

                {

                   
e.KeyChar = (char)0;   //处理非法字符

                }

            }

       
}

 

private void TextBox_KeyPress(object sender,
KeyPressEventArgs e)

   {

   
if(e.KeyChar!=8&&!Char.IsDigit(e.KeyChar))

    {

     
e.Handled = true;

    }

   }

或者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')//这是允许输入退格键

{

if((e.KeyChar<'0')||
(e.KeyChar>'9'))//这是允许输入0-9数字

{

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;

                }

            }     

       
}

 

 

 

利用ASCII码处理办法、

{

           
if ((e.KeyChar <= 48 || e.KeyChar >=57) && (e.KeyChar !=
8) && (e.KeyChar != 46))

              e.Handled = true;

================48
代表0，57代表9，8代表空格，46代表小数点

}