C# Find and Delete system restore points

SysRestoreDelete.cs

using System.Management;
using System.Runtime.InteropServices;

        [DllImport("Srclient.dll")]
        public static extern int DeleteRestorePoint(int index);
        private void SearchAndDestroySystemRestore()
        {
        
            //Find sequence numbers of system restore points
            
            System.Management.ManagementClass objClass = new System.Management.ManagementClass("\\\\.\\root\\default", "systemrestore", new System.Management.ObjectGetOptions());
            System.Management.ManagementObjectCollection objCol = objClass.GetInstances();
            String[] sequencenums = new String[100]; 
            int c = 0;
            foreach (System.Management.ManagementObject objItem in objCol)
            {
                sequencenums[c] = (((uint)objItem["sequencenumber"]).ToString());
                c++;
            }

            //Delete them
            while (c >= 0)
            {
                DeleteRestorePoint(Convert.ToInt32(sequencenums[c]));
                c--;
            }

        }