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[KA NMC]

What I'm trying to do in a listview is calculate the time now from a time in the table and place that result into a column on the grid for each record.
I was able to do this great using a datagrid, I'm exploring into the listview world and I cant seem to figure out how to do this...here is my code

Function fncDaysOpen()
 
        Dim row As Integer
              Try
            For row = 0 To Mydataset3.Tables(0).Rows.Count - 1
 
'Convert DateTime String              
                Dim order_date As String
                order_date = lstGrid.Items(row).SubItems(2).Text
                Dim conv As DateTime
                conv = System.Convert.ToDateTime(order_date)
 
                Dim d1 As DateTime = conv
                Dim d2 As DateTime = System.DateTime.Today
 
                Dim subtract, absday
                subtract = 0
                Select Case DatePart("w", d1)
                    Case 1
                        subtract = subtract + 1
                    Case 7
                        subtract = subtract + 2
                End Select
 
                Select Case DatePart("w", d2)
                    Case 1
                        subtract = subtract + 2
                    Case 7
                        subtract = subtract + 1
                End Select
                absday = DateDiff("d", d1, d2) - 1
 
                fncDaysOpen = absday - CInt(2 * (absday \ 7))
 
               'I get My Error Right Here - when placing results for each rec.
 
                lstGrid.Items(row).SubItems(7).Text = fncDaysOpen     
 
                           Next row
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Function<b></b>

Thanks for any help

[Plater]

First off, why are you doing all that date part work?
DateTime objects can be subtracted from eachother

dim t as TimeSpan
t= (TimeSpan)(DateTime.Now-saveddatetime)
dim numdays as Double
numdays=t.TotalDays
 
'now you have a double with the total number of whole(and fractional!) days inbetween the two dates. Feel free to round off as you wish.
 

Secondly,
Does your listgrid have as many rows as your dataset already? Do they have a 7th subitem?

[KA NMC]

First off, why are you doing all that date part work?
DateTime objects can be subtracted from eachother

dim t as TimeSpan
t= (TimeSpan)(DateTime.Now-saveddatetime)
dim numdays as Double
numdays=t.TotalDays
 
'now you have a double with the total number of whole(and fractional!) days inbetween the two dates. Feel free to round off as you wish.
 

Secondly,
Does your listgrid have as many rows as your dataset already? Do they have a 7th subitem?

Thanks for that Code Snippet I'll give that a shot...
Yes grid has as many rows as my dataset. Rows 0 - 6 is coming from the database - row 7 is what I created to store the calculations of Date.Now - row 2.

Thanks for the help and the suggestion.

[Plater]

ahh, if your listview is bound to a datasource, you cannot add columns/rows to it. What you can do as an easy workaround, is in your SQL query, get another column that you can use as scratch.
So if you have "SELECT * FROM MYTABLE" you would say "SELECT *, myIDColumn as [Computed Column] FROM MYTABLE"
And then you would have an extra column called "Computed Column" that you can over-write the data in to be your computed value.

[KA NMC]

OHHHH.....I'll give that a shot...Question? how would I do this if I have to create two columns - syntax?? - "Select * myIDcolumn as [Computed Column_one], [Computed Column_two] Frm Mytable"

I'll definetly give this a shot. Thanks for your help.

ahh, if your listview is bound to a datasource, you cannot add columns/rows to it. What you can do as an easy workaround, is in your SQL query, get another column that you can use as scratch.
So if you have "SELECT * FROM MYTABLE" you would say "SELECT *, myIDColumn as [Computed Column] FROM MYTABLE"
And then you would have an extra column called "Computed Column" that you can over-write the data in to be your computed value.

[Plater]

Well let's say you have a table with the following columns:
ID | fname | lname | uname
-----------------------------------------

"SELECT *"
would return those 4 columns as:
("ID", "fname", "lname", "uname")

"SELECT *, ID as [Computed Column]"
would return those 4 columns plus an additional column as:
("ID", "fname", "lname", "uname", "Computed Column")

"SELECT *, ID as [Computed Column], ID as [Computed Column2]"
would return those 4 columns plus 2 additional columns as:
("ID", "fname", "lname", "uname", "Computed Column", "Computed Column2")

[KA NMC]

Got it thanks...For all your help...Now I just got to get it nested with another table like my datagrid. I dont think I'm a fan of Listviews yet...alot I need to learn. Thanks Again.

Well let's say you have a table with the following columns:
ID | fname | lname | uname
-----------------------------------------

"SELECT *"
would return those 4 columns as:
("ID", "fname", "lname", "uname")

"SELECT *, ID as [Computed Column]"
would return those 4 columns plus an additional column as:
("ID", "fname", "lname", "uname", "Computed Column")

"SELECT *, ID as [Computed Column], ID as [Computed Column2]"
would return those 4 columns plus 2 additional columns as:
("ID", "fname", "lname", "uname", "Computed Column", "Computed Column2")