DropDownList操作;ListBox操作;动态创建控件;Response.Write("欢迎学习ASP.NET''!");

1 DropDownList操作;

2 ListBox操作;

3 动态创建控件;

4 Response.Write("欢迎学习ASP.NET''!");

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1 DropDownList操作;(向右选择,向上移,向下移选项;)

if(DropDown1.Items.Count > 1)

{

ListItem Item = DropDown1.SelectedItem;

DropDown1.Items.Remove(Item);

String val = DropDown1.SelectedItem.Value ;

String text = DropDown1.SelectedItem.Text;

Label1.Text = val + text;

}

else

{

DropDown1.Items.Clear();

Label1.Text = "";

}

2 ListBox操作;(向右选择,向上移,向下移选项;)

private void Movebtn_Click(object sender, System.EventArgs e)

{

int Count = ListBox1.Items.Count;

int Index = 0;

for(int i=0;i<Count-1;i++)

{

ListItem Item = ListBox1.Items[Index];

if(ListBox1.Items[Index].Selected == true)

{

ListBox1.Items.Remove(Item);

ListBox2.Items.Add(Item);

Index--;

}

Index++;

}

}

private void Upbtn_Click(object sender, System.EventArgs e)

{

//若不是第一行则上移

if( ListBox1.SelectedIndex > 0 )

{

string name = ListBox1.SelectedItem.Text;

string ID = ListBox1.SelectedItem.Value;

int index = ListBox1.SelectedIndex;

ListBox1.SelectedItem.Text = ListBox1.Items[index-1].Text;

ListBox1.SelectedItem.Value = ListBox1.Items[index-1].Value;

ListBox1.Items[index-1].Text = name;

ListBox1.Items[index-1].Value = ID;

ListBox1.SelectedIndex --;

}

}

private void Downbtn_Click(object sender, System.EventArgs e)

{

//若不是最后一行则下移

if( ListBox1.SelectedIndex >= 0 && ListBox1.SelectedIndex < ListBox1.Items.Count-1 )

{

string name = ListBox1.SelectedItem.Text;

string ID = ListBox1.SelectedItem.Value;

int index = ListBox1.SelectedIndex;

ListBox1.SelectedItem.Text = ListBox1.Items[index+1].Text;

ListBox1.SelectedItem.Value = ListBox1.Items[index+1].Value;

ListBox1.Items[index+1].Text = name;

ListBox1.Items[index+1].Value = ID;

ListBox1.SelectedIndex ++;

}

}

3 动态创建控件;

private void Addbtn_Click(object sender, System.EventArgs e)

{

DropDownList DropDown = new DropDownList();

PlaceHolder1.Controls.Clear();

PlaceHolder1.Controls.Add(DropDown);

DropDown.ID="ControlID";

DropDown.Width=200;

DropDown.Items.Add(new ListItem("北京","0"));

DropDown.Items.Add(new ListItem("上海","1"));

DropDown.Items.Add(new ListItem("河北","2"));

ViewState["AddControl"] = true;

}

4 Response.Write("欢迎学习ASP.NET''!");