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有没有办法在blazor子组件中判断级联参数是否已更改?_Blazor_Webassembly_Cascading - Fatal编程技术网

有没有办法在blazor子组件中判断级联参数是否已更改?

有没有办法在blazor子组件中判断级联参数是否已更改?,blazor,webassembly,cascading,Blazor,Webassembly,Cascading,有没有办法在blazor子组件中判断级联参数是否已更改?我在主布局中有一个组合框,我正在尝试将所选值级联到子组件。但不确定如何从子组件判断值何时更改。这可能吗 // MainLayout.razor file // <CascadingValue Value="@selectedAddress.Id"> // @Body // </CascadingValue> The index.razor file is what

有没有办法在blazor子组件中判断级联参数是否已更改?我在主布局中有一个组合框,我正在尝试将所选值级联到子组件。但不确定如何从子组件判断值何时更改。这可能吗

// MainLayout.razor file

//    <CascadingValue Value="@selectedAddress.Id">
//          @Body
//    </CascadingValue>

The index.razor file is what is accessing the cascading parameter.
//MainLayout.razor文件
//    
//@Body
//    
index.razor文件是访问级联参数的文件。

是的,没问题。您可以在变量的
get;设置

儿童剃须刀

@Message
    
@code {
    int _ID;
    [CascadingParameter]
    public int ID {
        get { return _ID; }
        set {   int lastValue = _ID;        // HERE //
                _ID = value; 
                if (lastValue != value) DoChange(); }
    }
    string Message = "";
    void DoChange()
    {
        Message = "Value has been changed to " + _ID;
    }
}
<CascadingValue Value="CurrentValue">
    <CascadeChild />
</CascadingValue>

<button @onclick="ChangeCurrentValue">Change</button>

@code {
    int CurrentValue;
    Random rand = new Random();

    void ChangeCurrentValue()
    {
        CurrentValue = rand.Next();
    }
}
家长剃须刀

@Message
    
@code {
    int _ID;
    [CascadingParameter]
    public int ID {
        get { return _ID; }
        set {   int lastValue = _ID;        // HERE //
                _ID = value; 
                if (lastValue != value) DoChange(); }
    }
    string Message = "";
    void DoChange()
    {
        Message = "Value has been changed to " + _ID;
    }
}
<CascadingValue Value="CurrentValue">
    <CascadeChild />
</CascadingValue>

<button @onclick="ChangeCurrentValue">Change</button>

@code {
    int CurrentValue;
    Random rand = new Random();

    void ChangeCurrentValue()
    {
        CurrentValue = rand.Next();
    }
}

改变
@代码{
int电流值;
Random rand=新的Random();
void ChangeCurrentValue()
{
CurrentValue=rand.Next();
}
}