CopyListBoxItem从一个ListBox到另一个

Question

我有两个ListBoxes。我想将SelectedItem从第一个ListBox复制到第二个。

为什么这段代码不起作用？

    private void frm_addDispatchBoard2_Load(object sender, EventArgs e)
    {
        using(propertiesManagementDataContext db = new propertiesManagementDataContext())
        {
            var Buildings = db.Buildings.Select(q => new { q.BuildingLandNumber, q.BuildingId });

            listBox_allBuildings.DataSource = Buildings;
            listBox_allBuildings.DisplayMember = "BuildingLandNumber";
            listBox_allBuildings.ValueMember = "BuildingId";
        }          
    }

    private void btn_addBuilding_Click(object sender, EventArgs e)
    {
        if(listBox_allBuildings.SelectedIndex > 0)
        {
            listBox_selectedBuildings.Items.Add(listBox_allBuildings.SelectedItem);            
        }
    }

我得到的结果：

Answer 1

尝试这个我不确定你为什么要寻找包含但如果你真的需要看看SelectedValue和SelectedItem之间的区别

  

在此处使用此代码作为测试，以查看期望值是否显示在MessageBox

中

string selected = listBox_allBuildings.GetItemText(listBox_allBuildings.SelectedValue);    
MessageBox.Show(selected);

这可以帮助您查看右侧列表框中的值

private void btn_addBuilding_Click(object sender, EventArgs e)
{
    if(listBox_allBuildings.SelectedIndex != -1)
    {
       var selected = listBox_allBuildings.GetItemText(listBox_allBuildings.SelectedValue);     
       listBox_selectedBuildings.Items.Add(selected);
    }
}