如何动态加控件
我想在窗体上，动态地
首先，有一个文本框，有一个下拉框，需要当1文本框中有文字的时候，就动态在他后面出来一个下拉框


当然程序里也可以获取到这个下拉框和文本框的ID什么的

其实我就是想做一个动态的SQL语句的组合

就好像大家去搜索什么东西的时候，高级搜索界面里面的那些一样~

------解决方案--------------------
给你这段，参考一下吧
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
namespace eg42_addCtrlAtRuntimeApp
{
public partial class MainForm : Form
{
private int count;
public MainForm()
{
InitializeComponent();
}
void Btn_MouseEnter(object sender, EventArgs e)
{
Button currentButton = (Button)sender;
currentButton.BackColor = Color.Blue;
}
void Btn_MouseLeave(object sender, EventArgs e)
{
Button currentButton = (Button)sender;
currentButton.BackColor = System.Windows.Forms.Control.DefaultBackColor;
}
void Btn_Click(object sender, MouseEventArgs e)
{
Button currentButton = (Button)sender;
txt_msg.Text = "你点击了" + currentButton.Text;
}
void Btn_addButtonMouseClick(object sender, MouseEventArgs e)
{
count += 2; int localX = this.btn_addButton.Height * count; int localY = 10 * count;
Button toAddButton = new Button();
toAddButton.Name = "Button" + count;
toAddButton.Text = "按钮" + count + "";
toAddButton.Location = new Point(localX, localY);
toAddButton.MouseEnter += new EventHandler(this.Btn_MouseEnter);
toAddButton.MouseLeave += new EventHandler(this.Btn_MouseLeave);
toAddButton.MouseClick += new MouseEventHandler(this.Btn_Click);
this.Controls.Add(toAddButton);
}
}
}
------解决方案--------------------

C# code

            TextBox txtbox = new TextBox();
            txtbox.Parent = this;
            txtbox.Left = 0;
            txtbox.Top = 0;
            ComboBox combox = new ComboBox();
            combox.Parent = this;
            combox.Left = txtbox.Right + 10;
            combox.Top = 0;
            combox.Visible = false;
            txtbox.Tag = combox;
            txtbox.TextChanged += new EventHandler(
                delegate(object obj, EventArgs ex)
                {
                    ((ComboBox)((TextBox)obj).Tag).Visible = !string.IsNullOrEmpty(((TextBox)obj).Text);
                }
                );

------解决方案--------------------
C# code
 ComboBox cbo = new ComboBox();
            cbo.DropDownStyle = ComboBoxStyle.DropDownList;
            cbo.Location = new System.Drawing.Point(73, 171);
            cbo.Name = "cboCont";
            this.Controls.Add(cbo);


        绑定combobox

------解决方案--------------------
有一个文本框，有一个下拉框，需要当1文本框中有文字的时候，就动态在他后面出来一个下拉框


完全不需要动态，动态的事件涉及到页面生命周期，很不好操作。

页面上隐藏掉下拉框。你只需要的文本框的TextChange事件判断，

if（！string.isnullorEmpty(text)）
{
  dropdownlist.visible = true; //设置下拉框显示。
}