Ado.net 数据库读取文件

string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
using(SqlConnection conn = new SqlConnection(connStr))
{
using(SqlDataAdapter adapter = new SqlDataAdapter("select * from userInfo", conn))
{
DataTable da = new DataTable();
adapter.Fill(da);
if (da.Rows.Count > 0)
{
StringBuilder sb = new StringBuilder();
foreach (DataRow row in da.Rows)
{
sb.AppendFormat("<tr><td>{0}</td><td>{1}</td><td>{2}</td></tr>", row["ID"].ToString(), row["Name"].ToString(), row["UserName"].ToString());
}

//读取模板文件，替换占位符
string filePath = context.Request.MapPath("UserInfoList.html");
string fileContent = File.ReadAllText(filePath);
fileContent = fileContent.Replace("要替换的占位符", sb.ToString());
context.Response.Write(fileContent);
}
else
{
context.Response.Write("暂无数据");
}
}
}