asp.net 下拉列表无级数据绑定实现代码

private string toadd = "├".<br><br>private void getarticlecategory(string pid)
{
sqlconnection conn = new sqlconnection("server=.;database=test;uid=sa;pwd=;");
string sql = "select articlesgroup_id,groupname from articlesgroup where articlesgroup_parent_id=@pid order by groupname";
sqlcommand cmd = new sqlcommand(sql, conn);
sqlparameter pid = new sqlparameter("@pid", sqldbtype.int);
pid.value = pid;
cmd.parameters.add(pid);
conn.open();
sqldatareader sdr = cmd.executereader();
while (sdr.read())
{
this.dropdownlist1.items.add(new listitem(toadd + " " + sdr[1].tostring(), sdr[0].tostring()));
toadd += "─┴";
this.getarticlecategory(sdr[0].tostring());
toadd = toadd.substring(0, toadd.length - 2);
}
sdr.close();
conn.close();
}

在page_load里调用

程序代码

protected void page_load(object sender, eventargs e)
{
this.keyword.attributes.add("onfocus","if( this.value=='key key key') {this.value='' };");
if (!page.ispostback)
{
this.getarticlecategory("0");
}
this.dropdownlist1.items.insert(0, new listitem("search all", "all"));
}