Hi,

Page 542:

PostBack.Text += handlerName

NoPostBack.Text += handlerName

QUESTION: why is "+=" needed and not just "=" ? If I coded this myself, I would never think to use the + ...

???

Chp 15 is tough. I saw this also but going to pass on it. But now that I see it posted, yes, I am wondering now also.

There is nothing in the labels, so why does the label.Text need a "+=" to work properly?

Hi nanonerd and JWalsh,

Take another look at Chapter 5, page 156. += is used to append a new value to whatever was already there in the label. With using just =, you would overwrite the existing value.

On the first event, the label is indeed empty so an equals sign would suffice. However, since this method is called multiple times during the same request, an equals sign would overwrite the previous value on each call. This in turn would only output the name of the very last event that executed. By using +=, the Text property is expanded on each call, giving you a list of the event handlers that have been called.

Hope this helps,

Imar

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Imar Spaanjaars
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Author of Beginning ASP.NET 4.5 : in C# and VB, Beginning ASP.NET Web Pages with WebMatrix
and Beginning ASP.NET 4 : in C# and VB.
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