验证本机的excel版本的C#代码

/// <summary>
/// 安装的excel的版本,0为没有安装,大于1说明安装了多个.
/// </summary>
/// <returns></returns>
public static list<string> excelversion()
{
list<string> list = new list<string>();
list<string> lisemp = new list<string>();
list<string> listvison = new list<string>();
registrykey rk = registry.localmachine;
registrykey akey = rk.opensubkey(@"software\\microsoft\\office");
registrykey csk;
string str;
hashtable hash = new hashtable();
string[] ss = akey.getsubkeynames();
foreach (string s in ss)
{
string strem = @"software\\microsoft\\office" + @"\\" + s;
csk = rk.opensubkey(strem);
string[] csd = csk.getsubkeynames();
foreach (string sk in csd)
{
if (sk == "excel")
{
str = strem + @"\\" + "excel";
list.add(str);
lisemp.add(s);
}
}
}
if (list != null)
{
for (int index = 0; index < list.count; index++)
{
list[index] = list[index] + @"\\installroot\\";
registrykey f = rk.opensubkey(list[index]);
if (f != null)
{
listvison.add(lisemp[index]);
}
}
}
return listvison;
}