数据源连接未重置 [英] DataSource connection is not reset

问题描述

我创建了一个包含以下组件(button1，button2和列表框)的简单项目.

按钮1的代码

I created a simple project with following components (button1, button2 and listbox).

The code for button 1

listBox1.Items.Clear();
                      
            RegistryKey OurKey = Registry.LocalMachine;
            OurKey = OurKey.OpenSubKey(@"SOFTWARE\\MyRegistry\\", true);

            if (OurKey != null)
            {
                  foreach (string sub in OurKey.GetSubKeyNames())
                {
                    listBox1.Items.Add(sub);
                }
                OurKey = OurKey.OpenSubKey(@"SOFTWARE\\MyRegistry\\", false);
            }
            else
            {
                listBox1.Items.Add("Key does not exist");
            }

按钮2的代码

The code for button 2

listBox1.Items.Clear();
openFileDialog1.InitialDirectory = @"C:\MyFile\MyFiles";
            openFileDialog1.Filter = "text|*.txt|All|*.*";
            openFileDialog1.FilterIndex = 1;
            openFileDialog1.Multiselect = true;
          
            if (openFileDialog1.ShowDialog() != DialogResult.Cancel)
            {
               string[] lines = File.ReadAllLines(openFileDialog1.FileName);

                listBox1.DataSource = lines;
                

            }
                     //listBox1.DataBindings.Clear();
                    // listbox1.DataSource=null

当我单击按钮1时，将正确填充列表框，然后单击按钮2，列表也将正确填充；当单击按钮2时，列表也将正确填充.但是，如果再次单击按钮1，则会出现错误设置DataSource属性时无法修改项目集合".
我尝试使用"listbox1.DataSource = null"或"listBox1.DataBindings.Clear()"，但没有运气

When I click button one, the listbox is populated correctly, then I click button 2, the list is populated correctly as well; however, if I click button 1 again I get an error "Item collection cannot be modified when the DataSource property is set".
I tried to use "listbox1.DataSource=null" or "listBox1.DataBindings.Clear()" but no luck
Any help will be greatly appreciated

推荐答案

一旦将数据源添加到列表框中，就无法修改ListBox.Items集合.相反，您可以修改原始源.

例如，如果您的列表框绑定到通用字符串列表

Once you add a DataSource to your listbox, you cannot modify the ListBox.Items collection. Instead, you can modify the original source.

For example, if your listbox is bound to a generic list of strings

List<string> myList = new List<string>(); 
myList.Add("Item 1"); 
myList.Add("Item 2"); 
myList.Add("Item 3");  

listBox1.DataSource = myList;</string></string>

这篇关于数据源连接未重置的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！