C# equivalent to TryCast

[clintonG]

Will somebody convert this for me...

System.Web.UI.H tmlControls.Htm lHead header;
header = TryCast(this.Pa ge.Header, System.Web.UI.H tmlControls.Htm lHead);

<%= Clinton Gallagher
NET csgallagher AT metromilwaukee. com
URL http://clintongallagher.metromilwaukee.com/
MAP http://wikimapia.org/#y=43038073&x=-...8&z=17&l=0&m=h

[Dustin Campbell]

System.Web.UI.H tmlControls.Htm lHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...

Best Regards,
Dustin Campbell
Developer Express Inc.

[clintonG]

Thanks...

<%= Clinton

"Dustin Campbell" <du*****@no-spam-pleasedevexpres s.comwrote in message
news:c1******** *************** ***@news.micros oft.com...

System.Web.UI.H tmlControls.Htm lHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...

Best Regards,
Dustin Campbell
Developer Express Inc.

[nick.fletcher]

You can also use the "is" keyword

System.Web.UI.H tmlControls.Htm lHead header;

if (this.PageHeade r is System.Web.UI.H tmlControls.Htm lHead)
{
header = (this.PageHeade r as
System.Web.UI.H tmlControls.Htm lHead);
}

On Nov 28, 7:58 am, "clintonG"
<csgallag...@RE MOVETHISTEXTmet romilwaukee.com wrote:

Thanks...

<%= Clinton

"Dustin Campbell" <dust...@no-spam-pleasedevexpres s.comwrote in messagenews:c1* *************** **********@news .microsoft.com. ..

System.Web.UI.H tmlControls.Htm lHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...

Best Regards,
Dustin Campbell
Developer Express Inc.

[Wiebe Tijsma]

This works fine as well, but I think the previous example has preference
because it will only cast the object once.

Wiebe Tijsma

ni***********@i inet.net.au wrote:

You can also use the "is" keyword

System.Web.UI.H tmlControls.Htm lHead header;

if (this.PageHeade r is System.Web.UI.H tmlControls.Htm lHead)
{
header = (this.PageHeade r as
System.Web.UI.H tmlControls.Htm lHead);
}

On Nov 28, 7:58 am, "clintonG"
<csgallag...@RE MOVETHISTEXTmet romilwaukee.com wrote:

>Thanks...

<%= Clinton

"Dustin Campbell" <dust...@no-spam-pleasedevexpres s.comwrote in messagenews:c1* *************** **********@news .microsoft.com. ..

>>System.Web.UI .HtmlControls.H tmlHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...
Best Regards,
Dustin Campbell
Developer Express Inc.

[Gabriel Lozano-Morán]

I am just curious on why you want to cast at all?

Gabriel Lozano-Morán

"clintonG" <cs*********@RE MOVETHISTEXTmet romilwaukee.com wrote in message
news:e5******** ******@TK2MSFTN GP02.phx.gbl...

Will somebody convert this for me...

System.Web.UI.H tmlControls.Htm lHead header;
header = TryCast(this.Pa ge.Header, System.Web.UI.H tmlControls.Htm lHead);

<%= Clinton Gallagher
NET csgallagher AT metromilwaukee. com
URL http://clintongallagher.metromilwaukee.com/
MAP http://wikimapia.org/#y=43038073&x=-...8&z=17&l=0&m=h

[clintonG]

Can somebody explain why this cast and this form of cast is used?

// An object named header is derived (?) from the class HtmlHead
System.Web.UI.H tmlControls.Htm lHead header;

// Using the is keyword this instance of the PageHeader object is typed
// as an HtmlHead object allowing the instance of this.PageHeader object
// to "borrow" properties of an HtmlHead object
this.PageHeader is System.Web.UI.H tmlControls.Htm lHead

I read the "is a" and the "has a" relationship but I don't understand
the "why a" and this is where I burn out.
<%= Clinton Gallagher
"Wiebe Tijsma" <wi*********@CA PITALStijsma.co mwrote in message
news:%2******** ********@TK2MSF TNGP02.phx.gbl. ..

>
This works fine as well, but I think the previous example has preference
because it will only cast the object once.

Wiebe Tijsma

ni***********@i inet.net.au wrote:

>You can also use the "is" keyword

System.Web.UI. HtmlControls.Ht mlHead header;

if (this.PageHeade r is System.Web.UI.H tmlControls.Htm lHead)
{
header = (this.PageHeade r as
System.Web.UI. HtmlControls.Ht mlHead);
}

On Nov 28, 7:58 am, "clintonG"
<csgallag...@R EMOVETHISTEXTme tromilwaukee.co mwrote:

>>Thanks...

<%= Clinton

"Dustin Campbell" <dust...@no-spam-pleasedevexpres s.comwrote in
messagenews:c 1************** ************@ne ws.microsoft.co m...

System.Web.U I.HtmlControls. HtmlHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...
Best Regards,
Dustin Campbell
Developer Express Inc.

[nick.fletcher]

In fact - the compiled msil is exactly the same but the example which
doesnt use "is" makes one extra read and write to the stack (tho not
being an expert in reading msil I couldnt tell you why)

try it :-)

On Nov 28, 11:51 am, Wiebe Tijsma <wiebeREM...@CA PITALStijsma.co m>
wrote:

This works fine as well, but I think the previous example has preference
because it will only cast the object once.

Wiebe Tijsma

nick.fletc...@i inet.net.au wrote:

You can also use the "is" keyword

System.Web.UI.H tmlControls.Htm lHead header;

if (this.PageHeade r is System.Web.UI.H tmlControls.Htm lHead)
{
header = (this.PageHeade r as
System.Web.UI.H tmlControls.Htm lHead);
}

On Nov 28, 7:58 am, "clintonG"
<csgallag...@RE MOVETHISTEXTmet romilwaukee.com wrote:

Thanks...

<%= Clinton

"Dustin Campbell" <dust...@no-spam-pleasedevexpres s.comwrote in messagenews:c1* *************** **********@news .microsoft.com. ..

>System.Web.UI. HtmlControls.Ht mlHead header;
header = this.Page.Heade r as System.Web.UI.H tmlControls.Htm lHead;
if (header == null)
// cast failed...
else
// cast succeeded...
Best Regards,
Dustin Campbell
Developer Express Inc.

[clintonG]

I found the code in VB while trying to learn what options were available to
me to write into the head of the page when using Themes. I need to control
writing linked style sheets *after* the link element generated by the Theme.

<%= Clinton Gallagher

"Gabriel Lozano-Morán" <ab***@frontbri dge.comwrote in message
news:%2******** ********@TK2MSF TNGP03.phx.gbl. ..

>I am just curious on why you want to cast at all?

Gabriel Lozano-Morán

"clintonG" <cs*********@RE MOVETHISTEXTmet romilwaukee.com wrote in message
news:e5******** ******@TK2MSFTN GP02.phx.gbl...

>Will somebody convert this for me...

System.Web.UI. HtmlControls.Ht mlHead header;
header = TryCast(this.Pa ge.Header, System.Web.UI.H tmlControls.Htm lHead);

<%= Clinton Gallagher
NET csgallagher AT metromilwaukee. com
URL http://clintongallagher.metromilwaukee.com/
MAP http://wikimapia.org/#y=43038073&x=-...8&z=17&l=0&m=h

[clintonG]

I picked up the code snippet from Accessing the Html Header in ASP.NET 2.0
[1]. I'm trying to make sense of how to use it when using Themes.

<%= Clinton Gallagher

[1] http://weblogs.asp.net/pscott/archiv...30/424039.aspx

"clintonG" <cs*********@RE MOVETHISTEXTmet romilwaukee.com wrote in message
news:%2******** ********@TK2MSF TNGP02.phx.gbl. ..

>I found the code in VB while trying to learn what options were available to
me to write into the head of the page when using Themes. I need to control
writing linked style sheets *after* the link element generated by the
Theme.

<%= Clinton Gallagher

"Gabriel Lozano-Morán" <ab***@frontbri dge.comwrote in message
news:%2******** ********@TK2MSF TNGP03.phx.gbl. ..

>>I am just curious on why you want to cast at all?

Gabriel Lozano-Morán

"clintonG" <cs*********@RE MOVETHISTEXTmet romilwaukee.com wrote in
message news:e5******** ******@TK2MSFTN GP02.phx.gbl...

>>Will somebody convert this for me...

System.Web.UI .HtmlControls.H tmlHead header;
header = TryCast(this.Pa ge.Header, System.Web.UI.H tmlControls.Htm lHead);

<%= Clinton Gallagher
NET csgallagher AT metromilwaukee. com
URL http://clintongallagher.metromilwaukee.com/
MAP http://wikimapia.org/#y=43038073&x=-...8&z=17&l=0&m=h