Winform TextBox中只能輸入數字的幾種經常使用方法(C#)

方法一： 
 
private void tBox_KeyPress(object sender, KeyPressEventArgs e) 
 
 { 
            if (e.KeyChar == 0x20) e.KeyChar = (char)0;  //禁止空格鍵 
            if ((e.KeyChar == 0x2D) && (((TextBox)sender).Text.Length == 0)) return;   //處理負數 
            if (e.KeyChar > 0x20) 
            { 
                try 
                { 
                    double.Parse(((TextBox)sender).Text + e.KeyChar.ToString()); 
                } 
                catch 
                { 
                    e.KeyChar = (char)0;   //處理非法字符 
                } 
            } 
} 
 
方法二： 
 
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; 
    } 
 
} 
 
方法三: 
 
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e) 
{ 
if(e.KeyChar!='\b')//這是容許輸入退格鍵 
{ 
if((e.KeyChar<'0')||(e.KeyChar>'9'))//這是容許輸入0-9數字 
{ 
e.Handled = true; 
} 
} 
} 
 
方法四: 
 
private void textBox1_Validating(object sender, CancelEventArgs e)  
{  
const string pattern = @"^\d+\.?\d+{1}quot;;  
string content = ((TextBox)sender).Text;  
 
if (!(Regex.IsMatch(content, pattern)))  
{  
errorProvider1.SetError((Control)sender, "只能輸入數字!");  
e.Cancel = true;  
}  
else  
errorProvider1.SetError((Control)sender, null);  
} 
 
方法五: 
 
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; 
} 
 
} 
 
方法六： 
 
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;//消除不合適字符 
            } 
            else if (Char.IsPunctuation(e.KeyChar)) 
            { 
                if (e.KeyChar != '.' || this.textBox1.Text.Length == 0)//小數點 
                { 
                    e.Handled = true; 
                } 
                if (textBox1.Text.LastIndexOf('.') != -1) 
                { 
                    e.Handled = true; 
                } 
            }       
  }   
 
方法七: 
 
利用ASCII碼處理辦法、 
{ 
 
            if ((e.KeyChar <= 48 || e.KeyChar >=57) && (e.KeyChar != 8) && (e.KeyChar != 46)) 
              e.Handled = true; 
================48表明0，57表明9，8表明空格，46表明小數點 
}