测试文本框是否存在 C# WPF
Test if TextBox Exists C# WPF
我想测试之前在代码中创建的 TextBox
是否存在。这个TextBox
是在一个"if test"中创建的,这就是为什么我要测试它是否存在的原因。但是我不知道如何测试它是否存在,因为我无法调用 TextBox
名称,因为它不存在..
private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (((ComboBoxItem)typeproduit.SelectedItem).Content.ToString() == "Isolant")
{
TextBox EpIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
MyPage.Children.Add(EpIsolant);
Label EpIsolantLabel = new Label
{
Content = "Ep isolant (mm)",
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 260, 0, 0)
};
MyPage.Children.Add(EpIsolantLabel);
}
else
{
// I want to test it here
// And if it exists, I want to remove it from MyPage.Children
}
}
感谢您的帮助!我找不到有关 Google
的任何帮助
PS : 当我尝试更改可见性时,它仍然不起作用:
private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
TextBox EpIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
MyPage.Children.Add(EpIsolant);
Label EpIsolantLabel = new Label
{
Content = "Ep isolant (mm)",
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 260, 0, 0)
};
MyPage.Children.Add(EpIsolantLabel);
EpIsolant.Visibility = Visibility.Hidden;
EpIsolantLabel.Visibility = Visibility.Hidden;
if (((ComboBoxItem)typeproduit.SelectedItem).Content.ToString() == "Isolant")
{
EpIsolant.Visibility = Visibility.Visible;
EpIsolantLabel.Visibility = Visibility.Visible;
}
else
{
EpIsolant.Visibility = Visibility.Hidden;
EpIsolantLabel.Visibility = Visibility.Hidden;
}
}
如前所述,您可以考虑将 Button
的 Visibility
或 IsEnabled
属性 更改为 hide/disable。
但是如果你想坚持你的解决方案,你可以去掉方法外的变量:
private TextBox _epIsolant;
那你可以给它赋一个对象:
_epIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
您还可以检查它是否是在您的方法中创建的:
if(_epIsolant == null)
{
...
}
我想测试之前在代码中创建的 TextBox
是否存在。这个TextBox
是在一个"if test"中创建的,这就是为什么我要测试它是否存在的原因。但是我不知道如何测试它是否存在,因为我无法调用 TextBox
名称,因为它不存在..
private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (((ComboBoxItem)typeproduit.SelectedItem).Content.ToString() == "Isolant")
{
TextBox EpIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
MyPage.Children.Add(EpIsolant);
Label EpIsolantLabel = new Label
{
Content = "Ep isolant (mm)",
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 260, 0, 0)
};
MyPage.Children.Add(EpIsolantLabel);
}
else
{
// I want to test it here
// And if it exists, I want to remove it from MyPage.Children
}
}
感谢您的帮助!我找不到有关 Google
的任何帮助PS : 当我尝试更改可见性时,它仍然不起作用:
private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
TextBox EpIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
MyPage.Children.Add(EpIsolant);
Label EpIsolantLabel = new Label
{
Content = "Ep isolant (mm)",
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 260, 0, 0)
};
MyPage.Children.Add(EpIsolantLabel);
EpIsolant.Visibility = Visibility.Hidden;
EpIsolantLabel.Visibility = Visibility.Hidden;
if (((ComboBoxItem)typeproduit.SelectedItem).Content.ToString() == "Isolant")
{
EpIsolant.Visibility = Visibility.Visible;
EpIsolantLabel.Visibility = Visibility.Visible;
}
else
{
EpIsolant.Visibility = Visibility.Hidden;
EpIsolantLabel.Visibility = Visibility.Hidden;
}
}
如前所述,您可以考虑将 Button
的 Visibility
或 IsEnabled
属性 更改为 hide/disable。
但是如果你想坚持你的解决方案,你可以去掉方法外的变量:
private TextBox _epIsolant;
那你可以给它赋一个对象:
_epIsolant = new TextBox
{
Width = 100,
Height = 29,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = new Thickness(209, 294, 0, 0)
};
您还可以检查它是否是在您的方法中创建的:
if(_epIsolant == null)
{
...
}