Hi,

I use HtmlBuilder to get an Image map as a string and pass it to the client browser but are having some difficulties.

First this is how I use the HtmlBuilder class:

HtmlBuilder hb = new HtmlBuilder(_flc);
map = hb.CreateImageMap("chart");
 

This string is returned and assigned in another class to a attribute of that class, imgMap. Here is how I want to "print to screen", Note phImageMap is a PlaceHolder instance on the custom control also containing the image of the graph:

LiteralControl ltc = new LiteralControl();
ltc.Text = imgMap;
phImageMap.Controls.Add(ltc);
 

The first problem came when the string returned contained some escape characters, for example:

"\t<MAP NAME=\"chart\">\r\n
\t\t<AREA SHAPE=\"RECT\" COORDS=\"316,182,366,232\"\r\n
\t\t\tHREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=28\" TARGET=\"_self\" TITLE=\"\">\r\n
\t\t<AREA SHAPE=\"RECT\" COORDS=\"316,32,366,82\"\r\n
\t\t\tHREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=27\" TARGET=\"_self\" TITLE=\"\">\r\n
\t\t<AREA SHAPE=\"RECT\" COORDS=\"166,257,216,307\"\r\n
\t\t\tHREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=26\" TARGET=\"_self\" TITLE=\"\">\r\n
\t\t<AREA SHAPE=\"RECT\" COORDS=\"166,107,216,157\"\r\n
\t\t\tHREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=25\" TARGET=\"_self\" TITLE=\"\">\r\n
\t\t<AREA SHAPE=\"RECT\" COORDS=\"16,182,66,232\"\r\n
\t\t\tHREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=24\" TARGET=\"_self\" TITLE=\"\">\r\n
\t</MAP>\r\n"
 

Now this project is using DOTNETNUKE and it seems that the html generating modules did not like these, so I wrote some regexp to clean those out.

Now at this point when I take the value of the string variable that gets passed(that is cleaned) and explicitly print that, example:

phImageMap.Controls.Add(new LiteralControl("<MAP NAME=\"chart\"><AREA SHAPE=\"RECT\" COORDS=\"316,32,366,82\" HREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=28\" TARGET=\"_self\" TITLE=\"\"><AREA SHAPE=\"RECT\" COORDS=\"166,332,216,382\" HREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=27\" TARGET=\"_self\" TITLE=\"\"><AREA SHAPE=\"RECT\" COORDS=\"166,182,216,232\" HREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=26\" TARGET=\"_self\" TITLE=\"\"><AREA SHAPE=\"RECT\" COORDS=\"166,32,216,82\" HREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=25\" TARGET=\"_self\" TITLE=\"\"><AREA SHAPE=\"RECT\" COORDS=\"16,182,66,232\" HREF=\"/fburg/Default.aspx?TabId=523&CtrlView=ProcessSummary&ProcessId=10&ProcessGraphImage=Show&id=24\" TARGET=\"_self\" TITLE=\"\"></MAP>"));
 

the image map is generated over the image and it works very well. But when I assign the the variable "imgMap"(like showen in the second code snipped) it does not generated the image map.

Now I have two questions. The first is if there is a way to make HtmlBuilder not generate the string with all the escape characters etc? I did not see anything of the kind in the documentation. The second question is if someone can point me at the weird string assignment problem? I know this is likely something very silly but we can't find the problem.

Kind Regards.

Hi,

I've tried multiple ways of writing the string now, including the one you suggested. No luck. Even when using:

Response.Write(imgMap);
 

it did not work, so I doubt it's something to do with the Literal or LiteralControl classes.

I was thinking that it might be .NET that does something with the string variable. Since, like I stated previously, when I explicitly put the data retrieved from memory dumps into the code, using Response.Write and PlaceHolder it work perfectly. So we tried:

String.Format("{0}", imgMap);
 

before writing it, but yet again this did not work.

Any other ideas no this problem? Maybe some way of recreating the string like the String.Format attempt?

Yes the imgMap variable is set and the map is written now as seen when viewing source. The problem was a loading issue with the string of the map and the image data, due to this being a control in a control in a page(being a control) etc...

So with this done I thought my troubles was over but not quite yet. For some reason the string generated by HTMLBuilder(without any manipulation) works perfectly in Firefox but not IE7. Any ideas on why? This is the code as seen in the source through IE7's "view source":

<div id="processGraphImage">
<img id="dnn_ctr882_ProcessMainView_ctrlProcessSummary_ProcessGraphImage_processImage" usemap="#chart" src="http://localhost/fburg/Default.aspx?TabId=523&amp;CtrlView=ProcessSummary&amp;ProcessId=10&amp;ProcessGraphImage=Show" alt="" border="0" />

<MAP NAME="#chart">


<AREA SHAPE="RECT" COORDS="316,32,366,82"



HREF="/fburg/TASKMANAGEMENT/Process/tabid/523/CtrlView/ProcessSummary/ProcessId/10/Default.aspx?id=28" TARGET="_self" TITLE="">


<AREA SHAPE="RECT" COORDS="166,332,216,382"



HREF="/fburg/TASKMANAGEMENT/Process/tabid/523/CtrlView/ProcessSummary/ProcessId/10/Default.aspx?id=27" TARGET="_self" TITLE="">


<AREA SHAPE="RECT" COORDS="166,182,216,232"



HREF="/fburg/TASKMANAGEMENT/Process/tabid/523/CtrlView/ProcessSummary/ProcessId/10/Default.aspx?id=26" TARGET="_self" TITLE="">


<AREA SHAPE="RECT" COORDS="166,32,216,82"



HREF="/fburg/TASKMANAGEMENT/Process/tabid/523/CtrlView/ProcessSummary/ProcessId/10/Default.aspx?id=25" TARGET="_self" TITLE="">


<AREA SHAPE="RECT" COORDS="16,182,66,232"



HREF="/fburg/TASKMANAGEMENT/Process/tabid/523/CtrlView/ProcessSummary/ProcessId/10/Default.aspx?id=24" TARGET="_self" TITLE="">

</MAP>

</div>
 

Firefox's source looks exactly the same and works as stated above. In IE7 the the image is displayed but you can't click on the nodes.

Hi Stoyo,

Yes with the # not at the start of the name it does the same. Note that the map does not work in Firefox with the #. About the div, it's used to be without one and does not change IE7's behaviour without it. Also, there are no more regexp in my code. So the string I try to print is the exact one I get from HTMLBuilder.

Thanks.