小编cmj*_*cmj的帖子

int stxval = 0x02; //found this value on wikipedia
string mystring = "Hello";

StringBuilder builder = new StringBuilder(mystring);
builder.Append(stxval);

此处在字符串构建器"2Hello"中附加.如何以这种形式"Hello"获取字符串？

protected void Button1_Click(object sender, EventArgs e)
{
    TableRow tb = new TableRow();
    TableCell tc = new TableCell();

    DropDownList db = new DropDownList();
    db.Items.Add("Bangalore");
    db.Items.Add("Mandya");
    db.Items.Add( "Hassan");

    tc.Controls.Add(db);
    tb.Controls.Add(tc);

    Table1.Controls.Add(tb);

    db.SelectedIndexChanged += db_SelectedIndexChanged;
    db.AutoPostBack = true;
}

private void db_SelectedIndexChanged(object sender, EventArgs e)
{
    label.text = "welcome";
}

当此代码在Button1_Click事件db_SelectedIndexChanged中执行时,不执行.但是,当我Button1_Click在Page_Load事件中放置相同的代码块时,db_SelectedIndexChanged执行.

这背后可能是什么原因？