并非所有的代码路径都返回值?解决方案

并非所有的代码路径都返回值???
我写了一个新闻读取的类，但是出现标题所出的问题。
这是我的详细代码：
前台：
<table border="1">
<tr><td style="width: 293px" runat="server" id="tt1">&nbsp;</td></tr>
</table>
后台
 protected void Page_Load(object sender, EventArgs e)
  {
  string str = "select top 5 * from news where type_ids=51 order by id desc";
  access.yj(str,tt1);
  }

调用的类：
public static string yj(string str,HtmlTableCell tt)
  {
  SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["GirlsysConnectionString"].ConnectionString);//连接数据库
  try
  {
  conn.Open();
  SqlCommand cmd = new SqlCommand(str, conn);
  SqlDataReader dea = cmd.ExecuteReader();
  while (dea.Read())
  { 
  tt.InnerText +="<a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);
  return tt.InnerText;
  }
  }
  catch
  {
  return tt.InnerText;
  }
  finally
  {
  conn.Close();
  }
  }
谢谢各位了
 

[解决办法]
while (dea.Read())
{
tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);
return tt.InnerText;
} 

如果while 里面没有执行，又没有出异常，就出问题了！
[解决办法]
这一句的位置不对！
return tt.InnerText;
[解决办法]

C# code

public static string yj(string str,HtmlTableCell tt)     {         SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["GirlsysConnectionString"].ConnectionString);//连接数据库         try         {             conn.Open();             SqlCommand cmd = new SqlCommand(str, conn);             SqlDataReader dea = cmd.ExecuteReader();             while (dea.Read())             {                 tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);                 return tt.InnerText;             }         }         catch         {             return tt.InnerText;         }         finally         {             conn.Close();         }     }
[解决办法]
public static string yj(string str,HtmlTableCell tt)
   {
       SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["GirlsysConnectionString"].ConnectionString);// 连接数据库
       try
       {
           conn.Open();
           SqlCommand cmd = new SqlCommand(str, conn);
           SqlDataReader dea = cmd.ExecuteReader();
           while (dea.Read())
           {
               tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);
              
           }
           return tt.InnerText;
       }
       catch
       {
           return tt.InnerText;
       } 
 
       finally
       {
           conn.Close();
       }
   }
[解决办法]
改:
C# code
public static string yj(string str,HtmlTableCell tt)     {         SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["GirlsysConnectionString"].ConnectionString);//连接数据库         try         {             conn.Open();             SqlCommand cmd = new SqlCommand(str, conn);             SqlDataReader dea = cmd.ExecuteReader();             while (dea.Read())             {                 tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);                            }         }         catch         {             //return tt.InnerText;         }         finally         {             conn.Close();         }  return tt.InnerText;     }
[解决办法]
你的代码写错了:
  while (dea.Read())  
           {  
               tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>"   +access.Substr(dea["title"].ToString(), 0, 11);  
               return tt.InnerText;  
           }  
应该是这样的吧:
  while (dea.Read())  
           {  
               tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>"   +access.Substr(dea["title"].ToString(), 0, 11);  
           }
  return tt.InnerText;  

[解决办法]
public static string yj(string str,HtmlTableCell tt)
   {
       SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["GirlsysConnectionString"].ConnectionString);// 连接数据库
       try
       {
           conn.Open();
           SqlCommand cmd = new SqlCommand(str, conn);
           SqlDataReader dea = cmd.ExecuteReader();
           while (dea.Read())
           {
               tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);
               return tt.InnerText;
           }
return string.empty;
       }
       catch
       {
           return tt.InnerText;
       }
       finally
       {
           conn.Close();
       }
   }
[解决办法]
C# code
while (dea.Read())             {                 tt.InnerText +=" <a href=\"news_look.aspx?id=" + dea["id"] + "\" target=_blank>" + access.Substr(dea["title"].ToString(), 0, 11);                 [color=#FF0000]return tt.InnerText;[/color]             }