初始化字符串格式不符合规范
web.config文件配置：

XML code

 <appSettings>    <add key="FCKeditor:BasePath" value="~/fckeditor/"/>    <add key="FCKeditor:UserFilesPath" value="/Files/" />      </appSettings>  <connectionStrings>    <add name="decoraconn"  connectionString="server=localhost;uid=sa;pwd=251209;database=decorations" providerName="System.Data.SqlClient"/>  </connectionStrings>

按钮代码：

C# code

protected void btnLogin_Click(object sender, EventArgs e)    {        string connstring =System.Configuration.ConfigurationManager.ConnectionStrings["decoraconn"].ConnectionString;        SqlConnection con = new SqlConnection("connstring");        con.Open();        SqlCommand cmd = new SqlCommand();        cmd.CommandType=CommandType.Text;        cmd.CommandText ="select * from Admin where account="+tbName.Text;        SqlDataReader dr = cmd.ExecuteReader();        if (dr.Read())        {            if (dr["password"].ToString() == tbPwd.Text)            {                Response.Redirect("index.aspx");            }            else {                lblMessge.Visible = true;                lblMessge.Text = "登陆失败，密码错误！";            }        }        else {            lblMessge.Visible = true;            lblMessge.Text = "登陆失败，用户不存在！";        }        dr.Close();    }

运行的时候提示：从索引 0 处开始，初始化字符串的格式不符合规范。是怎么一回事呀，设置不对么

[解决办法]
SqlConnection con = new SqlConnection("connstring") 改为
SqlConnection con = new SqlConnection(connstring);

去掉双引号