您好我显示多条记录,当我按下按钮点击时,它们没有正确降序。
文本被添加到数据库中并显示但是我在页面上显示了两组记录,并且插入的文本被下推到第一个多记录的底部。
如何更正此问题,以便我只在页面上获得一次返回,并将注释(来自db的文本)设置为desc。
代码:
protected void Page_Load(object sender, EventArgs e)
{
string theUserId = Session["UserID"].ToString();
PopulateWallPosts(theUserId);
}
private void PopulateWallPosts(string userId)
{
using (OdbcConnection cn = new OdbcConnection("Driver={MySQL ODBC 3.51 Driver}; Server=localhost; Database=gymwebsite2; User=x; Password=x;"))
{
cn.Open();
using (OdbcCommand cmd = new OdbcCommand("SELECT Wallpostings FROM WallPosting WHERE UserID=" + userId + " ORDER BY idWallPosting DESC", cn))
{
using (OdbcDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
System.Web.UI.HtmlControls.HtmlGenericControl div = new System.Web.UI.HtmlControls.HtmlGenericControl("div");
div.Style["float"] = "left";
Image img = new Image();
img.ImageUrl = "~/userdata/2/uploadedimage/batman-for-facebook.jpg";
img.AlternateText = "Test image";
div.Controls.Add(img);
test1.Controls.Add(div);
System.Web.UI.HtmlControls.HtmlGenericControl div1 = new System.Web.UI.HtmlControls.HtmlGenericControl("div");
div1.InnerText = String.Format("{0}", reader.GetString(0));
div1.Style["float"] = "left";
test1.Controls.Add(div1);
System.Web.UI.HtmlControls.HtmlGenericControl div2 = new System.Web.UI.HtmlControls.HtmlGenericControl("div");
div2.Style["clear"] = "both";
test1.Controls.Add(div2);
}
}
}
}
}
protected void Button1_Click(object sender, EventArgs e)
{
string theUserId = Session["UserID"].ToString();
using (OdbcConnection cn = new OdbcConnection("Driver={MySQL ODBC 3.51 Driver}; Server=localhost; Database=gymwebsite2; User=x; Password=x;"))
{
cn.Open();
using (OdbcCommand cmd = new OdbcCommand("INSERT INTO WallPosting (UserID, Wallpostings) VALUES (" + theUserId + ", '" + TextBox1.Text + "')", cn))
{
cmd.ExecuteNonQuery();
}
}
PopulateWallPosts(theUserId);
}
}
答案 0 :(得分:1)
只需在循环前清除占位符控件:
test1.Controls.Clear();
while (reader.Read())
{
...
}
答案 1 :(得分:0)
调用PopulateWallPosts(theUserId);在Page_Prerender上而不是在Load和on Click上两次。
PS您的代码易受SQL注入和XSS攻击。不要相信用户的输入:)