Question

c#中请教一个arraylist 用法

public string[] HelloWorld(string prefixText, int count)
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["con"].ToString ());
if (con.State == ConnectionState.Closed)
con.Open();
SqlCommand cmd = new SqlCommand("select top " + count + " name from revise where name like \'" + prefixText + "%\'", con);
SqlDataReader dr = cmd.ExecuteReader();
ArrayList s = new ArrayList();
while (dr.Read())
s.Add(dr[0].ToString());
return (string )s.ToArray();//这一行是错的，应该怎么写才是对的了
}

Answer 1

你在return前就把那个强制转换转换成了string字符串，而你的方法真正返回的是string[]数组，类型不一致

Answer 2

return (string[] )s.ToArray();//