wpf – 将Button的可见性绑定到两个文本框的内容的最简洁方法

<Text@L_675_1@ Text="{Binding TB1Text,Mode=TwoWay}" />
<Text@L_675_1@ Text="{Binding TB2Text,Mode=TwoWay}"/>
<Button Content="Lorem Ipsum" IsEnabled="{Binding ButtonIsEnableD}"/>

private String _TB1Text;
public String TB1Text
{
    get { return _TB1Text; }
    set
    {
        if (_TB1Text != value)
        {
            _TB1Text = value;
            PropertyChanged.Notify(() => this.TB1Text);
            PropertyChanged.Notify(() => this.buttonIsEnabled);
        }
    }
}

private String _TB2Text;
public String TB2Text
{
    get { return _TB2Text; }
    set
    {
        if (_TB2Text != value)
        {
            _TB2Text = value;
            PropertyChanged.Notify(() => this.TB2Text);
            PropertyChanged.Notify(() => this.buttonIsEnabled);
        }
    }
}

public bool ButtonIsEnabled
{
    get { return !(String.IsNullOrEmpty(TB1Text) && String.IsNullOrEmpty(TB2Text)); }
}

(PropertyChanged.Notify只是一种扩展方法,可以在不需要传递字符串的情况下引发事件)

不会使用绑定而是使用MultiDatatrigger：

<Text@L_675_1@ Name="tb1"/>
<Text@L_675_1@ Name="tb2"/>
<Button Content="Lorem Ipsum">
    <Button.Style>
        <Style TargetType="Button">
            <Style.triggers>
                <MultiDatatrigger>
                    <MultiDatatrigger.Conditions>
                        <Condition Binding="{Binding Text,ElementName=tb1}" Value="{x:Static sys:string.Empty}"/> 
                        <Condition Binding="{Binding Text,ElementName=tb2}" Value="{x:Static sys:string.Empty}"/> 
                    </MultiDatatrigger.Conditions>
                    <Setter Property="IsEnabled" Value="false"/>
                </MultiDatatrigger>
            </Style.triggers>
        </Style>
    </Button.Style>
</Button>

顺便说一句,你不需要一个Text@L_675_1@案例的转换器：

<Button Content="Lorem Ipsum" IsEnabled="{Binding Text.Length,ElementName=myText@L_675_1@}"/>