是否可以初始化控件的List< T>.标记中的属性? [英] Is it possible to initialize a Control's List<T> property in markup?

问题描述

假设我们有以下内容:

public enum RenderBehaviors
{
    A,
    B,
    C,
}

public class MyControl : Control
{
    public List<RenderBehaviors> Behaviors { get; set; }

    protected override void Render(HtmlTextWriter writer)
    {
        // output different markup based on behaviors that are set
    }
}

是否可以在ASPX/ASCX标记中初始化Behaviors属性?即:

Is it possible to initialize the Behaviors property in the ASPX/ASCX markup? i.e.:

<ns:MyControl runat="server" ID="ctl1" Behaviors="A,B,C" />

在这种情况下，

子类化不是一个选项(行为"的实际意图与该示例略有不同).当我尝试以这种方式初始化属性时，WebForms会生成解析器错误.相同的问题可以应用于其他List类型(int，字符串).

Subclassing is not an option in this case (the actual intent of the Behaviors is slightly different than this example). WebForms generates a parser error when I try to initialize the property in this way. The same question could be applied to other List types (int, strings).

推荐答案

进一步研究之后，我发现WebForms确实可以使用TypeConverter.类型或属性需要正确修饰，如此相关问题.

After researching this further, I found that WebForms does use a TypeConverter if it can find it. The type or the property needs to be decorated properly, as detailed in this related question.

我结束了类似的事情:

public class MyControl : Control
{
    private readonly HashSet<RenderBehaviors> coll = new HashSet<RenderBehaviors>();

    public IEnumerable<RenderBehaviors> Behaviors { get { return coll; } }

    public string BehaviorsList
    {
        get { return string.Join(',', coll.Select(b => b.ToString()).ToArray()); }
        set
        {
            coll.Clear();
            foreach (var b in value.Split(',')
                .Select(s => (RenderBehvaior)Enum.Parse(typeof(RenderBehavior), s)))
            {
                coll.Add(b);
            }
        }
    }
}

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