C# 一个窗口的label如何读取另一个窗口中listbox里面某个值，并可以同步？
有两个窗体 form1 ，form2（平级关系，上面还有个总form），form2中label.text要读取form1中listbox中某一行（例如第三行）的值。而且当listbox第三行数值被修改（删除），label能自动同步修改值（删除）。
label form代码
public AddRenameWindow addrename { get; set; }
//connect with addrename form 's data
public void AlterWindow_Load(object sender, EventArgs e)
{
//show teams' name in addrenmae form on this form
label4.Text = AddRenameWindow.a[0];
label5.Text = AddRenameWindow.a[1];
label6.Text = AddRenameWindow.a[2];
label7.Text = AddRenameWindow.a[3];
label8.Text = AddRenameWindow.a[4];
label9.Text = AddRenameWindow.a[5];
label10.Text = AddRenameWindow.a[6];
label11.Text = AddRenameWindow.a[7];
label12.Text = AddRenameWindow.a[8];
label13.Text = AddRenameWindow.a[9];
label14.Text = AddRenameWindow.a[10];
label15.Text = AddRenameWindow.a[11];
label16.Text = AddRenameWindow.a[12];
label17.Text = AddRenameWindow.a[13];
label18.Text = AddRenameWindow.a[14];
label19.Text = AddRenameWindow.a[15];
label20.Text = AddRenameWindow.a[16];
label21.Text = AddRenameWindow.a[17];
}
listbox form代码
public AlterWindow alter { get; set; }
public static string[] a = new string[30];
public void button4_Click(object sender, EventArgs e)
{
AlterWindow alter = new AlterWindow();
for (int index = 0; index < listBox1.Items.Count; index++)
{
a[index] = Convert.ToString(listBox1.Items[index]);
//MessageBox.Show(a[i].ToString());
}
this.Close();
}
}
自己用蠢办法做出来了，虽然蠢但是同步功能完美。
``
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;
namespace Q759361
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.Show();
InputBox ib = Application.OpenForms.Cast<Form>().FirstOrDefault(x => x is InputBox) as InputBox;
if (ib == null)
{
ib = new InputBox();
ib.textBox1.TextChanged += TextBox1_TextChanged;
ib.Top = this.Top;
ib.Left = this.Left + this.Width + 10;
ib.Visible = true;
}
}
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left; // x position of upper-left corner
public int Top; // y position of upper-left corner
public int Right; // x position of lower-right corner
public int Bottom; // y position of lower-right corner
}
[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr SendMessage(IntPtr hWnd, int Msg, int wParam, out RECT lParam);
public const int LB_GETITEMRECT = 408;
private void Button3_Click(object sender, EventArgs e)
{
if (listBox1.SelectedItem != null)
{
listBox1.Items.Remove(listBox1.SelectedItem);
foreach (Form item in Application.OpenForms)
{
//if (item is InputBox) { item.Close(); break; }
if (item is InputBox) { (item as InputBox).label2.Text = ""; }
}
}
}
//private void Button2_Click(object sender, EventArgs e)
//{
// if (listBox1.SelectedItem == null)
// return;
// InputBox ib = Application.OpenForms.Cast<Form>().FirstOrDefault(x => x is InputBox) as InputBox;
// if (ib == null)
// {
// ib = new InputBox();
// ib.textBox1.TextChanged += TextBox1_TextChanged;
// }
// ib.Top = this.Top;
// ib.Left = this.Left + this.Width + 10;
// ib.textBox1.Text = listBox1.Text;
// if (!ib.Visible) ib.Show(this);
//}
private void TextBox1_TextChanged(object sender, EventArgs e)
{
if (listBox1.SelectedItem != null)
listBox1.Items[listBox1.SelectedIndex] = (sender as TextBox).Text;
}
private void Button1_Click(object sender, EventArgs e)
{
int i = listBox1.Items.Add("");
listBox1.SelectedIndex = i;
button2.PerformClick();
}
private int modidx;
private void ListBox1_DoubleClick(object sender, EventArgs e)
{
RECT rect;
if (listBox1.SelectedItem != null)
{
SendMessage(listBox1.Handle, LB_GETITEMRECT, listBox1.SelectedIndex, out rect);
textBox1.BorderStyle = BorderStyle.FixedSingle;
textBox1.Left = listBox1.Left + rect.Left + 2;
textBox1.Width = rect.Right - rect.Left - 4;
textBox1.Top = listBox1.Top + rect.Top + 2;
textBox1.Height = rect.Bottom - rect.Top - 4;
textBox1.Text = listBox1.SelectedItem.ToString();
textBox1.SelectAll();
textBox1.Visible = true;
textBox1.Focus();
modidx = listBox1.SelectedIndex;
}
}
private void TextBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == '\r')
{
e.Handled = false;
listBox1.Items[modidx] = textBox1.Text;
textBox1.Visible = false;
}
}
private void TextBox1_Validated(object sender, EventArgs e)
{
listBox1.Items[modidx] = textBox1.Text;
textBox1.Visible = false;
}
private void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
{
InputBox ib = Application.OpenForms.Cast<Form>().FirstOrDefault(x => x is InputBox) as InputBox;
if (ib != null)
{
ib.label2.Text = listBox1.Text;
}
}
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Q759361
{
public partial class InputBox : Form
{
public InputBox()
{
InitializeComponent();
}
private void Button1_Click(object sender, EventArgs e)
{
Close();
}
private void Label2_TextChanged(object sender, EventArgs e)
{
label2.Visible = (label2.Text != "");
button1.Visible = label2.Visible;
}
}
}
说下思路吧
方法一：在form1中先查找获取当前的form2，然后在form1的listbox修改/删除事件中添加对该form2上的label的删改操作。
方法二：在主窗口定义一个公共变量，form1修改，form2定时读取
能想到的就这些了
定义一个事件，form1的listbox改变的时候触发该事件。form2定义一个函数修改label的值。主窗口负责将form1的事件，连接到form2的函数上
给你个思路，自定义事件（委托）去监听listbox的变化