限制長度:設定maxlength屬性

遮蔽非數字鍵輸入:新增keypress事件

private void textBox1_KeyPress(object sender, KeyPressEventArgs e){

e.Handled = !(Char.IsNumber(e.KeyChar) || e.KeyChar == "\b");

}

替換全形(中文)數字字元為半形(英文)字元:新增textchange事件

private void textBox1_TextChanged(object sender, EventArgs e){

for (int i=0;i

if (textBox1.Text[i] >= "0" && textBox1.Text[i]

textBox1.Text = textBox1.Text.Replace(textBox1.Text[i], (char)(textBox1.Text[i] - "0" + "0"));

}

門道我說不出多少,辦法也比較笨,看看是否符合要求