# Overlay collection

**URL:** <https://community.thinkgeo.com/t/overlay-collection/3248>\
**Category:** WPF\
**Created:** [July 8, 2012, 6:49pm UTC](https://community.thinkgeo.com/t/overlay-collection/3248 "2012-07-08T18:49:54Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Phil1](https://community.thinkgeo.com/letter_avatar_proxy/v4/letter/p/848f3c/32.png) [@Phil1](https://community.thinkgeo.com/u/Phil1)\
**Post date:** [July 8, 2012, 6:49pm UTC](https://community.thinkgeo.com/t/overlay-collection/3248/1 "2012-07-08T18:49:54Z")

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Hi&nbsp;All,

I&nbsp;have&nbsp;come&nbsp;across&nbsp;something&nbsp;strange&nbsp;and&nbsp;cant&nbsp;explain&nbsp;it.

I&nbsp;was&nbsp;using&nbsp;the&nbsp;following&nbsp;line&nbsp;of&nbsp;code&nbsp;which&nbsp;worked&nbsp;perfectly&nbsp;well&nbsp;for&nbsp;a&nbsp;set&nbsp;of&nbsp;data:

_&nbsp;LayerOverlay&nbsp;staticOverlay&nbsp;=&nbsp;(LayerOverlay)wpfMap1.Overlays[overlayName];_  
  
  
  
With&nbsp;a&nbsp;different&nbsp;layer&nbsp;it&nbsp;doesnt&nbsp;work.&nbsp;I&nbsp;have&nbsp;found&nbsp;looping&nbsp;though&nbsp;all&nbsp;the&nbsp;overlays&nbsp;and&nbsp;checking&nbsp;if&nbsp;the&nbsp;names&nbsp;match&nbsp;and&nbsp;then&nbsp;assigning&nbsp;the&nbsp;overlay&nbsp;does&nbsp;though??

_LayerOverlay&nbsp;staticOverlay&nbsp;=&nbsp;new&nbsp;LayerOverlay();_  
  
  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;foreach&nbsp;(Overlay&nbsp;overlay&nbsp;in&nbsp;wpfMap1.Overlays)_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{_  
  
  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if&nbsp;(overlay&nbsp;!=&nbsp;null)_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{_  
  
  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if&nbsp;(overlay.Name&nbsp;==&nbsp;overlayName)_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;staticOverlay&nbsp;=&nbsp;(LayerOverlay)overlay;_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}_  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}_  
  
  
  
_&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}_

Isnt&nbsp;this&nbsp;doing&nbsp;exactly&nbsp;the&nbsp;same&nbsp;thing?

thanks

Phil

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<div class="post-metadata">

**Author:** ![David](https://community.thinkgeo.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@David](https://community.thinkgeo.com/u/David)\
**Post date:** [July 8, 2012, 10:08pm UTC](https://community.thinkgeo.com/t/overlay-collection/3248/2 "2012-07-08T22:08:33Z")

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Phil,&nbsp;  
&nbsp;&nbsp;  
&nbsp;&nbsp;&nbsp;The&nbsp;two&nbsp;ways&nbsp;of&nbsp;finding&nbsp;the&nbsp;overlay&nbsp;are&nbsp;not&nbsp;the&nbsp;same.&nbsp;&nbsp;When&nbsp;you&nbsp;use&nbsp;the&nbsp;indexer,&nbsp;Overlays[“Some&nbsp;Key”]&nbsp;it&nbsp;is&nbsp;searching&nbsp;for&nbsp;the&nbsp;overlay&nbsp;by&nbsp;its&nbsp;string&nbsp;key.&nbsp;&nbsp;It’s&nbsp;the&nbsp;string&nbsp;key&nbsp;that&nbsp;was&nbsp;created&nbsp;when&nbsp;you&nbsp;added&nbsp;the&nbsp;overlay&nbsp;to&nbsp;the&nbsp;collection,&nbsp;ie.&nbsp;Overlays.Add(“Some&nbsp;Key”,overlay).&nbsp;&nbsp;The&nbsp;name&nbsp;on&nbsp;the&nbsp;overlay&nbsp;is&nbsp;just&nbsp;a&nbsp;property&nbsp;that&nbsp;you&nbsp;can&nbsp;optionally&nbsp;set&nbsp;and&nbsp;has&nbsp;nothing&nbsp;to&nbsp;do&nbsp;with&nbsp;the&nbsp;collection&nbsp;look&nbsp;up&nbsp;by&nbsp;string.&nbsp;&nbsp;The&nbsp;name&nbsp;was&nbsp;added&nbsp;so&nbsp;you&nbsp;have&nbsp;along&nbsp;name&nbsp;that&nbsp;can&nbsp;be&nbsp;used&nbsp;for&nbsp;things&nbsp;like&nbsp;legends&nbsp;etc.&nbsp;  
&nbsp;&nbsp;  
&nbsp;Thanks,&nbsp;  
&nbsp;&nbsp;  
&nbsp;David&nbsp;Rehagen

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<div class="post-metadata">

**Author:** ![Phil1](https://community.thinkgeo.com/letter_avatar_proxy/v4/letter/p/848f3c/32.png) [@Phil1](https://community.thinkgeo.com/u/Phil1)\
**Post date:** [July 9, 2012, 5:40pm UTC](https://community.thinkgeo.com/t/overlay-collection/3248/3 "2012-07-09T17:40:14Z")

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ok&nbsp;thanks&nbsp;David

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**Author:** ![Gary2](https://community.thinkgeo.com/letter_avatar_proxy/v4/letter/g/49beb7/32.png) [@Gary2](https://community.thinkgeo.com/u/Gary2)\
**Post date:** [July 11, 2012, 5:51pm UTC](https://community.thinkgeo.com/t/overlay-collection/3248/4 "2012-07-11T17:51:04Z")

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Hello&nbsp;Phil.&nbsp;  
&nbsp;&nbsp;  
&nbsp;You&nbsp;are&nbsp;welcome,&nbsp;please&nbsp;feel&nbsp;free&nbsp;to&nbsp;let&nbsp;us&nbsp;know&nbsp;your&nbsp;problems.&nbsp;  
&nbsp;&nbsp;  
&nbsp;Regards,&nbsp;  
&nbsp;&nbsp;  
&nbsp;Gary