Winform TextBox中只能输入数字的几种常用方法(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 
                } 
            } 

 
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')//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; 



 
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, "只能输入数字!");  
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; 
                } 
            }       
  }   
 
方法七: 
 
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 
}

posted @ 2018-12-04 14:16  笑笑小白  阅读(5210)  评论(0编辑  收藏