C# WPF TextBox控制只能輸入某一範圍(比如0-100)的整數
阿新 • • 發佈:2019-01-24
基本原理是直接新增兩個事件,然後加上判斷:
1. KeyDown 2.TextChanged
話不多說,直接上程式碼:
前臺程式碼:
<TextBox x:Name="TextBoxForText" HorizontalAlignment="Left" Height="101" Margin="10,167,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="299" KeyDown="TextBoxForText_KeyDown" MaxLength="3" TextChanged="TextBoxForText_TextChanged">
後臺程式碼:
private void TextBoxForText_KeyDown(object sender, KeyEventArgs e) { TextBox txt = sender as TextBox; // 過濾按鍵 if ((e.Key >= Key.NumPad0 && e.Key <= Key.NumPad9)) { e.Handled = false; } else if (((e.Key >= Key.D0 && e.Key <= Key.D9))) { e.Handled = false; } else { e.Handled = true; } } private void TextBoxForText_TextChanged(object sender, TextChangedEventArgs e) { try { string strNum = TextBoxForText.Text; if ("" == strNum || null == strNum) { return; } int num = int.Parse(TextBoxForText.Text); TextBoxForText.Text = num.ToString(); if (num <= 100) { return; } else { TextBoxForText.Text = TextBoxForText.Text.Remove(2); TextBoxForText.SelectionStart = TextBoxForText.Text.Length; } } catch (Exception ex) { MessageBox.Show(ex.ToString()); } }