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The (ViewCatWebQueryOpen) agent
Here is the code for the (ViewCatWebQueryOpen) agent:

Sub Initialize

Dim s As New NotesSession
Dim doc As NotesDocument
Set doc = s.DocumentContext

Call DoPrevNextHTML (doc)

End Sub

Sub DoPrevNextHTML (doc As NotesDocument)

' Figure out how many docs are about to be displayed in the view or view catagegory being shown, and
' display where this set is in the view (e.g., docs 26-50 of 123), and display previous and/or next links as appropriate

Dim db As NotesDatabase
Dim v As NotesView, entry As NotesViewEntry

Dim intTotal As Integer, intStart As Integer, intCount As Integer, intNextStart As Integer, intPrevStart As Integer
Dim strCatParm As String, strNextlabel As String, intNextEnd As Integer, strNextParms As String, strPrevParms As String, strPrevLabel As String, intPrevEnd As Integer
Dim intNext As Integer, intPrev As Integer

Set db = doc.ParentDatabase
Dim vPath As Variant

'Set URL path for return
vPath=Evaluate({@ReplaceSubstring (@Subset (@DbName; -1); "\\" : " "; "/" : "+")})

'Parse out the four parameters passed in as part of the URL - View, Category, Start, and Count

vView = Evaluate ({@Middle (Query_String + "&"; "&View="; "&")}, doc)
vCat = Evaluate ({@Replacesubstring (@Middle (Query_String + "&"; "&Cat="; "&"); "+" ; " ")}, doc)
vStart = Evaluate ({@Middle (Query_String + "&"; "&Start="; "&")}, doc)
vCount = Evaluate ({@Middle (Query_String + "&"; "&Count="; "&")}, doc)

If vStart(0) = "" Then
intStart = 1
Else
intStart = Cint (vStart(0))
End If

'Default Count to 25 if one wasn't provided on URL

If vCount(0) = "" Then
intCount = 25
Else
intCount = Cint (vCount(0))
End If

'Use strCatParm for the navigation links built later in the agent. After the following code, it sould contain, for example,
'"&Cat=Political+Thought"

If vCat(0) = "" Then
strCatParm = ""
Else
doc.tempcat = vCat
vCat2 = Evaluate ({ @Replacesubstring (tempcat; " " ; "+") }, doc)
strCatParm = "&Cat=" + vCat2(0)
End If

'Get the view passed on the URL

Set v = db.GetView (vView(0))

'If there is no category the user is browsing, simply count all the documents in the view. If they are browing a category,
'use the GetEntryByKey method of NotesView to get the first document in a category and then count its siblings to get
'the total for that category

If vCat(0) = "" Then
'doc.PrevNext = "equals blank"
intTotal = v.AllEntries.Count

Else
'doc.prevNext = "else"
Set entry = v.GetEntryByKey(vCat(0))
intTotal = entry.SiblingCount

End If

'Determine if Previous and Next links are neded, and what the proper Start parameter is for both

If intStart = 1 Then
' No Prev button. Next = start plus count
intPrev = False
If intStart + intCount > intTotal Then
' No need for next button
intNext = False
Else
intNext = True
intNextStart = intStart + intCount
End If

Else
intPrev = True
If intStart + intCount > intTotal Then
' No next button
intNext = False
Else
intNext = True
intNextStart = intStart + intCount
End If
intPrevStart = intStart - intCount
If intPrevStart < 1 Then intPrevStart = 1
End If

'Build the HTML (opening and closing tags) for both "Prev" and "Next" links - to be used once verbiage for each
'link is decided upon

strHrefStart = {<A HREF="/} + vPath(0) + {/ViewCat?ReadForm&View=} + vView(0) + strCatParm
strHrefEnd = {</A>}

'Build the verbiage for the "Next" link. If there are less than Count items left to display, use "Last" instead of "Next"

If intTotal - intNextStart < intCount Then
strNextLabel = "Last " + Cstr (intTotal - intNextStart + 1) + " Items"
Else
strNextLabel = "Next " + Cstr (intCount) + " Items"
End If

'Build parameters for "Next" link

strNextParms = {&Start=} + Cstr (intNextStart) + "&Count=" + Cstr(intCount)

'Build verbiage for "Previous" link. If there are less then Count items left to display, use "First" instead of "Previous"

If intStart - intCount < 0 Then
strPrevLabel = "First " + Cstr (intCount) + " Items"
Else
strPrevLabel = "Previous " + Cstr (intCount) + " Items"
End If

'Build parameters for "Previous" link

strPrevParms = {&Start=} + Cstr (intPrevStart) + {&Count=} + Cstr (intCount)

'Write links to document if they are needed. If not, these fields will not contain values and will not be visible to users

If intPrev Then
doc.Prev = strHrefStart + strPrevParms + {">} + strPrevLabel + strHrefEnd
End If

If intNext Then
doc.Next = strHrefStart + strNextParms + {">} + strNextlabel + strHrefEnd
End If

'Build 'Items x through x of x' information

If (intStart + intCount - 1) > intTotal Then
intShowing = intTotal
Else
intShowing = intStart + intcount - 1
End If

'Write it to document

doc.TotalCount = "Items " + Cstr (intStart) + " through " + Cstr (intShowing) + " of " + Cstr (intTotal)

'Duplicate the links (provided there are any) and information below the view as well

doc.Prev_1 = doc.Prev
doc.Next_1 = doc.Next
doc.TotalCount_1 = doc.TotalCount

End Sub