ajout items d'un intance listview

Bonjour ,

voici le code
Code:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
 
 
   private void pictureBoxajoutsuppression_Click(object sender, EventArgs e)
        {
            Offre Form1Instance = new Offre();
            Offre Form1Instance2 ;
            //this.panel5.Controls.Add(Form1Instance.li
           // this.panel5 = new System.Windows.Forms.Panel(Form1Instance);
         //  Form1Instance.panel4.BackColor =  Color.FromArgb(193, 208, 48);
            this.panel5.Controls.Add(Form1Instance.panel4);
            Form1Instance.Grid4(Form1Instance.grid4, Form1Instance.panel3);
 
 
            Form1Instance.Offre_Load(Form1Instance, e);
            this.tabPage2.BackColor = Color.WhiteSmoke;
            //Form1Instance.listView2.Items.Clear();
 
 
            //this.tabPage2.Controls.Add(Form1Instance.panel4);
            //this.listView2.Groups.Clear();
            System.Windows.Forms.ListView.ListViewItemCollection collectionditems = new ListView.ListViewItemCollection(Form1Instance.listView2);
            //this.listView2.Items.CopyTo(Form1Instance.listView1.Items);
 
            for (int i = 0; i < this.listView2.Items.Count; i++)
            {
 
                lvi4 = Form1Instance.CreateListViewItem(this.listView2.Items[i].SubItems[0].Text, this.listView2.Items[i].SubItems[1].Text, this.listView2.Items[i].SubItems[2].Text, this.listView2.Items[i].SubItems[3].Text, this.listView2.Items[i].SubItems[4].Text, this.listView2.Items[i].SubItems[5].Text, this.listView2.Items[i].SubItems[6].Text, this.listView2.Items[i].SubItems[7].Text, this.listView2.Items[i].SubItems[8].Text, this.listView2.Items[i].SubItems[9].Text);
                //string nom = ((string)lvi4[i]).getnom();
                Form1Instance.listView2.Items.Add(this.listView2.Items);
                Form1Instance.listView2.li = lvi4;
                ListViewGroup groups = new ListViewGroup();
 
 
 
                ListView.ListViewItemCollection items = this.listView2.Items;
                Form1Instance.listView2.Items[i].Group = this.listView2.Items[i].Group;
 
 
                //Form1Instance.triergroup(Form1Instance.listView2);
 
            }
 
 
            Form1Instance.AficherTableau(Form1Instance.listView2);
            Form1Instance.changercouleur();
 
 
 
                for (int i10 = 0; i10 < Form1Instance.listView2.Items.Count; i10++)
                {
                    MessageBox.Show(Form1Instance.listView2.Items[i10].Group.ToString());
                }
 
 
        }
je bataille depuis un moment pour copier coller tout les items de ma nouvelle form dans la form de destination .

Quelqu'un peut t'il m'éclairer je patoge un peu la .

Merci de votre cou de pouce