Item index change in a drop down list (ddl) using VB.Net

In VB.Net, how can I change the index (0, 1, 2, 3...) of an item of a drop down list (ddl)?
My case: I want to change a specific item's index to "0" so it is the first in list.
p.s. Don't tell me to use Properties/Misc/Items because that wont work in this case is not that simple.  If anymore details are needed please let me know.
wmoralesAsked:
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gregoryyoungCommented:
sorry didnt mean to submit ... ddl.Items.Insert(0, item) will put it at the beginning.
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gregoryyoungCommented:
well one example would be to just move it in the items collection

tmp = ddl.Items[0]
ddl.Items[0] = ddl.Items[5]
ddl.Items[5] = tmp
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iboutchkineCommented:
is your ddl bound to some datasource?
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gregoryyoungCommented:
true I should have asked that if it is just change the index in the bound collection ...
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wmoralesAuthor Commented:
and I would declare the tmp variable as what
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wmoralesAuthor Commented:
yes is bound to a datasource but the last field the one I want to make first isn't I added after the databind, ddl.Items.Add("...")
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wmoralesAuthor Commented:
well yes the index of the last item of the collection to 0
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gregoryyoungCommented:
either object is fine for a generic move (you are only moving references not accessing the type) or whatever is in items ... (if binding you put your own classes)
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wmoralesAuthor Commented:
I kind of get your answer but to be sure ---> dim tmp as ?
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iboutchkineCommented:
if you don't kow how to dim your var , always dim it as Object. It is a little overhead, but it will work
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gregoryyoungCommented:
unless you are accessing properties :) then thats evil.
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iboutchkineCommented:
true
:(
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wmoralesAuthor Commented:
Sub FILLddl()
        Dim con As SqlConnection
        con = New SqlConnection("Server=localhost;uid=sa ;pwd= ; database=DATABASE")
        con.Open()

        Dim sql As String
        sql = "SELECT * FROM TABLE"

        Dim da As New SqlDataAdapter(sql, con)
        Dim ds As New DataSet

        da.Fill(ds, "DATABASE")

        ddl.DataSource = ds
        ddl.DataTextField = "TABLE"
        ddl.DataValueField = "FIELD"

        ddl.DataBind()

        'ITEM THAT I WANT TO CHANGE INDEX TO 0
        ddl.Items.Add("...")
End Sub
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wmoralesAuthor Commented:
and I do this because I can't have the "..." in the database
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wmoralesAuthor Commented:
or don't want to have... either way that’s that
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iboutchkineCommented:
You can make this ddl hidden and
create another unbound ddl where you will add your item and then everything from the hidden ddl
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gregoryyoungCommented:
please excuse C# code ...

            public static void FillDropDown(System.Web.UI.WebControls.DropDownList _ddl, string _Table, string _DisplayColumn, string _ValueColumn)
            {
                  string ConnectionString = EnterpriseObjects.EnterpriseApplication.Application.ConnectionString ;
                  SqlConnection Connection = new SqlConnection(ConnectionString);

                  SqlCommand objCommand = new SqlCommand("SELECT " + _DisplayColumn+ " as disp," + _ValueColumn + " as val FROM " + _Table, Connection);

                  Connection.Open();
                                                _ddl.Items.Add(new ListItem("...", "...")
                  SqlDataReader objReader = objCommand.ExecuteReader();
                  while(objReader.Read()) {
                        _ddl.Items.Add(new ListItem(objReader.GetValue(0).ToString(), objReader.GetValue(1).ToString()));
                  }
                  objReader.Close();
                  Connection.Close();
            }
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gregoryyoungCommented:
not the prettiest code but it will do exactly what you want ....
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wmoralesAuthor Commented:
I'm going to try the hidden concept first then look into the C# algorism.
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gregoryyoungCommented:
just add them to the Items collection by yourself thats all its doing

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gregoryyoungCommented:
Sub FILLddl()
        Dim con As SqlConnection
        con = New SqlConnection("Server=localhost;uid=sa ;pwd= ; database=DATABASE")
        con.Open()

        Dim sql As String
        sql = "SELECT * FROM TABLE"

        Dim da As New SqlDataAdapter(sql, con)
        Dim ds As New DataSet

        da.Fill(ds, "DATABASE")

        DataTable dt = ds.Tables("DATABASE")
        ddl.Items.Add(new ListItem("...", "..."))
        for i = 0 to dt.Rows.Count - 1
             ddl.Items.Add(new ListItem(dt.Rows(i)(whatever),dt.Rows(i)(whatever))
        end for

        ddl.DataBind()

        'ITEM THAT I WANT TO CHANGE INDEX TO 0
        ddl.Items.Add("...")
End Sub
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gregoryyoungCommented:
oops remove databind call ...
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wmoralesAuthor Commented:
I know I did that in another way:

Do While objDataReader.Read() = True
            strResultsHolder = objDataReader("FIELD")
            ddl.Items.Add(strResultsHolder)
Loop

I just want to have it without do's or for's
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wmoralesAuthor Commented:
I know... :)
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gregoryyoungCommented:
what do you think the databinding does ? :)
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wmoralesAuthor Commented:
More complete:

Sub FILLddl()

        Dim con As SqlConnection
        con = New SqlConnection("Server=localhost;uid=sa ;pwd= ; database=DATABASE")
        con.Open()

        Dim strSQL As String = "SELECT * FROM TABLE"
        Dim strResultsHolder As String

        Dim objCommand As New SqlCommand(strSQL, conINVENTORY)
        Dim objDataReader As SqlDataReader

        objDataReader = objCommand.ExecuteReader()

        'HERE THE ITEM'S INDEX IS 0 BUT IS NOT WHAT I WANT
        'THE WAY I SHOW U BEFORE IS WHAT I WANT... I KNOW I'M LOOKING FOR...
        '... TROUBLE WHERE THERE ISN'T ANY BUT HEY...
        ddlWORKPLACE_NAME.Items.Add("...")

        Do While objDataReader.Read() = True
            strResultsHolder = objDataReader("TABLE")
            ddL.Items.Add(strResultsHolder)

            'ddl.Fill(ds, "TABLE")
        Loop

End Sub
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mmarinovCommented:
if you use dataset and dataadapter just to retrieve data from the db why dont you use

Sub FILLddl()
        Dim con As SqlConnection
        con = New SqlConnection("Server=localhost;uid=sa ;pwd= ; database=DATABASE")
        con.Open()

        Dim sql As String
        sql = "SELECT * FROM TABLE"

        Dim da As New SqlDataAdapter(sql, con)
        Dim ds As New DataSet

        da.Fill(ds, "DATABASE")

        Dim dr as DataRow = ds.Tables(0).NewRow()
        ds.Tables(0).Rows.InsertAt( dr, 0 )

        ddl.DataSource = ds
        ddl.DataTextField = "TABLE"
        ddl.DataValueField = "FIELD"

        ddl.DataBind()

        'ITEM THAT I WANT TO CHANGE INDEX TO 0
        ddl.Items.Add("...")
End Sub

HTH
NSub FILLddl()
        Dim con As SqlConnection
        con = New SqlConnection("Server=localhost;uid=sa ;pwd= ; database=DATABASE")
        con.Open()

        Dim sql As String
        sql = "SELECT * FROM TABLE"

        Dim da As New SqlDataAdapter(sql, con)
        Dim ds As New DataSet

        da.Fill(ds, "DATABASE")

        ddl.DataSource = ds
        ddl.DataTextField = "TABLE"
        ddl.DataValueField = "FIELD"

        ddl.DataBind()

        'ITEM THAT I WANT TO CHANGE INDEX TO 0
        ddl.Items.Add("...")
End Sub


HTH
B..M
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wmoralesAuthor Commented:
is: objDataReader("FIELD") not TABLE
and the: 'ddl.Fill(ds, "TABLE") at the end is a comment ignore that
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mmarinovCommented:
sorry, i've missed it
just see if you can get something from the posted code - it is exactly what you want in your question.
I applogies that i didn't read all the posts carefully and i was missed the correction

B..M
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wmoralesAuthor Commented:
mmarinov
I tried what you said but what it does is that gives a blank item ("     '') that does have the index 0 but I don’t what a blank in my ddl and is not the item that I want to have it's index 0
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wmoralesAuthor Commented:
Don’t worry I did the same today with somebody else problem.
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wmoralesAuthor Commented:
There isn't any other way to change the index other from the solutions we already have isn’t... because with the hidden idea it would work yes, but then it hit me that what I have to do for that to work is the same thing a wanted to omit whit the original ddl in the first place... but thank you anyway.
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gregoryyoungCommented:
items.insert()

Public Overridable Sub Insert( _
   ByVal index As Integer, _
   ByVal item As Object _
) Implements IList.Insert

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mmarinovCommented:
yes my sample add a blank item to your ddl, because i don't know what exactly you want to add - it is just the mechanism
you can use dr(index) od dr(nameofcolumn) and set the needed value to it so when the ddl is binded you will receive the dr at index 0 with the appropriate value and text

B..M
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wmoralesAuthor Commented:
YOU GOT IT!!!
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wmoralesAuthor Commented:
Yes I know I figured it out
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wmoralesAuthor Commented:
So what do I do now do I press Accept on gregoryyoung's
answer?
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wmoralesAuthor Commented:
Yes?
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gregoryyoungCommented:
I dunno I have never asked a question :)
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wmoralesAuthor Commented:
In a nutshell it all comes down to using Insert and not Add.
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wmoralesAuthor Commented:
Thank you all, problem solve... NEXT!
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gregoryyoungCommented:
yep .. although you could still add and flip as earlier stated ...
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wmoralesAuthor Commented:
Lest stick to the Insert… :)
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