绑定没有克隆方法,是一种有效的复制方法

Ara*_*and 10 c# data-binding wpf clone

我希望复制一个绑定,这样我就可以在其上设置不同的源属性而不影响原始绑定.这只是将新绑定的所有属性设置为与旧的相同的情况吗?

spl*_*tor 13

这是我解决问题的方法:

public static BindingBase CloneBinding(BindingBase bindingBase, object source)
{
    var binding = bindingBase as Binding;
    if (binding != null)
    {
        var result = new Binding
                         {
                             Source = source,
                             AsyncState = binding.AsyncState,
                             BindingGroupName = binding.BindingGroupName,
                             BindsDirectlyToSource = binding.BindsDirectlyToSource,
                             Converter = binding.Converter,
                             ConverterCulture = binding.ConverterCulture,
                             ConverterParameter = binding.ConverterParameter,
                             //ElementName = binding.ElementName,
                             FallbackValue = binding.FallbackValue,
                             IsAsync = binding.IsAsync,
                             Mode = binding.Mode,
                             NotifyOnSourceUpdated = binding.NotifyOnSourceUpdated,
                             NotifyOnTargetUpdated = binding.NotifyOnTargetUpdated,
                             NotifyOnValidationError = binding.NotifyOnValidationError,
                             Path = binding.Path,
                             //RelativeSource = binding.RelativeSource,
                             StringFormat = binding.StringFormat,
                             TargetNullValue = binding.TargetNullValue,
                             UpdateSourceExceptionFilter = binding.UpdateSourceExceptionFilter,
                             UpdateSourceTrigger = binding.UpdateSourceTrigger,
                             ValidatesOnDataErrors = binding.ValidatesOnDataErrors,
                             ValidatesOnExceptions = binding.ValidatesOnExceptions,
                             XPath = binding.XPath,
                         };

        foreach (var validationRule in binding.ValidationRules)
        {
            result.ValidationRules.Add(validationRule);
        }

        return result;
    }

    var multiBinding = bindingBase as MultiBinding;
    if (multiBinding != null)
    {
        var result = new MultiBinding
                         {
                             BindingGroupName = multiBinding.BindingGroupName,
                             Converter = multiBinding.Converter,
                             ConverterCulture = multiBinding.ConverterCulture,
                             ConverterParameter = multiBinding.ConverterParameter,
                             FallbackValue = multiBinding.FallbackValue,
                             Mode = multiBinding.Mode,
                             NotifyOnSourceUpdated = multiBinding.NotifyOnSourceUpdated,
                             NotifyOnTargetUpdated = multiBinding.NotifyOnTargetUpdated,
                             NotifyOnValidationError = multiBinding.NotifyOnValidationError,
                             StringFormat = multiBinding.StringFormat,
                             TargetNullValue = multiBinding.TargetNullValue,
                             UpdateSourceExceptionFilter = multiBinding.UpdateSourceExceptionFilter,
                             UpdateSourceTrigger = multiBinding.UpdateSourceTrigger,
                             ValidatesOnDataErrors = multiBinding.ValidatesOnDataErrors,
                             ValidatesOnExceptions = multiBinding.ValidatesOnDataErrors,
                         };

        foreach (var validationRule in multiBinding.ValidationRules)
        {
            result.ValidationRules.Add(validationRule);
        }

        foreach (var childBinding in multiBinding.Bindings)
        {
            result.Bindings.Add(CloneBinding(childBinding, source));
        }

        return result;
    }

    var priorityBinding = bindingBase as PriorityBinding;
    if (priorityBinding != null)
    {
        var result = new PriorityBinding
                         {
                             BindingGroupName = priorityBinding.BindingGroupName,
                             FallbackValue = priorityBinding.FallbackValue,
                             StringFormat = priorityBinding.StringFormat,
                             TargetNullValue = priorityBinding.TargetNullValue,
                         };

        foreach (var childBinding in priorityBinding.Bindings)
        {
            result.Bindings.Add(CloneBinding(childBinding, source));
        }

        return result;
    }

    throw new NotSupportedException("Failed to clone binding");
}
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  • 绑定仅允许您设置ElementName,RelativeSource或Source之一.如果您尝试设置多个,则会抛出InvalidOperationException. (2认同)
  • 我在使用上面的代码时遇到了麻烦,除了我将源代码从旧的绑定复制到新的绑定.在我的例子中,绑定继承DataContext作为其源.当我复制源时,它显式设置null作为源,这显然导致不使用DataContext.要克服这个问题,请使用:'Source = binding.Source ?? DependencyProperty.UnsetValue; (2认同)

gin*_*boy 2

如果您找不到执行此操作的方法,请为绑定创建一个扩展。

    public static class BindingExtensions
{
    public static Binding Clone(this Binding binding)
    {
        var cloned = new Binding();
        //copy properties here
        return cloned;
    }
}

public void doWork()
{
    Binding b= new Binding();
    Binding nb = b.Clone(); 
}
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