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:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:
80:
81:
82:
83:
84:
85:

            private void BTsaveCurrList_Click(object sender, EventArgs e)
            {
                string selectedParty = CBparty.SelectedItem.ToString();
                string FileName = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) + "\\StepSaveItems.txt";
                string itemValue;

                
                
                StreamWriter writeFile = new StreamWriter(FileName);


                if (File.Exists(FileName))
                {
                    writeExistingContent();
                    writeFile.WriteLine("Party: " + selectedParty);
                    writeFile.WriteLine("--------------------------------------");


                    foreach (object itemo in CLBlist.CheckedItems)
                    {

                        itemValue = itemo.ToString();

                        if (File.Exists(FileName))
                        {

                            writeFile.WriteLine(itemValue);

                        }
                        else
                        {
                            writeFile.WriteLine(itemValue);

                        }

                    }

                    writeFile.WriteLine("--------------------------------------");
                    writeFile.WriteLine();
                }
                else
                {
                    writeFile.WriteLine("Party: " + selectedParty);
                    writeFile.WriteLine("--------------------------------------");


                    foreach (object itemo in CLBlist.CheckedItems)
                    {

                        itemValue = itemo.ToString();

                        if (File.Exists(FileName))
                        {

                            writeFile.WriteLine(itemValue);

                        }
                        else
                        {
                            writeFile.WriteLine(itemValue);

                        }

                    }

                    writeFile.WriteLine("--------------------------------------");
                    writeFile.WriteLine();
                }
                writeFile.Close();

            }


            public String writeExistingContent()
            {
                string existingContent = "";
                string FileName = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) + "\\StepSaveItems.txt";

                StreamReader readContent = new StreamReader(FileName);
                existingContent = readContent.ReadToEnd();
                readContent.Close();

                return existingContent;
            
            }					

1:
2:
3:
4:
5:
6:
7:
8:

if (File.Exists(FileName))
{
   writeFile.WriteLine(itemValue);
}
else
{
   writeFile.WriteLine(itemValue);
}