问题
I have a custom server control with a property of Title. When using the control, I'd like to set the value of the title in the aspx page like so:
<cc1:customControl runat="server" Title='<%= PagePropertyValue%>' >
more content
</cc1:customControl>
When I do this, however, I am getting the exact String <%= PagePropertyValue%> being displayed rather than the Property Value that I would like to see.
So after trying the databinding expression (as suggested below). I don't get the string literal that looked bad but I don't get anything else either.
<cc1:customControl runat="server" Title='<%# PagePropertyValue%>' >
more content
</cc1:customControl>
What do I need to do to my custom control to take this sort of value? Or is there something I need to do to the page.
回答1:
You cant. <%= %> will write the string directly to the response-stream, which happens after the server control is constructed. See this post for an explanation.
So its either codebehind, or <%# + databinding as Zachary suggests.
回答2:
As a followup to my own question, I have discovered that what I really wanted was to use ASP.NET Expressions using the <%$ syntax, since what I wanted to do was put in localized content.
This can be done with apparently no extra handling on the server control side.
<cc1:customControl runat="server" Title='<%$ Resouces: ResourceFile, ContentKey %>' >
more content and controls
</cc1:customControl>
This works just fine.
回答3:
Try using databinding syntax:
<%# PagePropertyValue %>
回答4:
For the bind property value to work correctly as suggested, you will have this in the aspx or ascx file :
<cc1:customControl runat="server" Title='<%# PagePropertyValue %>' >
more content
</cc1:customControl>
You will then need to actually bind data in your page wich you have to add this in you code behind file (code in C#)
protected void Page_Load(object sender, EventArgs e)
{
DataBind();
}
That way it will bind the data in your ascx or aspx file.
回答5:
Note that this is specific to control attributes. When using the <%= syntax outside control attributes meaning anywhere else in the page the syntax works as expected. So this <%=GetCapitalUserName()%> would call the correct method and inject the result of the call in the page.
来源:https://stackoverflow.com/questions/387167/how-do-i-make-my-asp-net-server-control-take-an-embedded-code-block-as-a-propert