Question

我在单独的线程上查询数据库，并在返回时调用线程安全调用。但是创造了一个例外 - 我做错了什么？

注意我也填充了列表视图但为了清晰起见而将其删除

 private void ThreadSafeListView()
    {


        if (this.listView1.InvokeRequired)
        {
            try
            {
                ThreadSafe Operation d = new ThreadSafeOperation(ThreadSafeListView);
                this.Invoke(d );
            }
            catch { }
        }
        else
        {


            listView1.Columns[0].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
            listView1.Columns[1].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
            listView1.Columns[2].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
            listView1.Columns[3].AutoResize(ColumnHeaderAutoResizeStyle.HeaderSize);
            listView1.Columns[4].AutoResize(ColumnHeaderAutoResizeStyle.HeaderSize);


        }
    }

异常细节= InvalidOperationException： “跨线程操作无效：控制'listView1'从其创建的线程以外的线程访问。”

Answer 1

抛出什么异常？如果它仍然是一个线程安全的异常，那么可能是因为你没有从需要调用的项调用。尝试：

listView1.Invoke(d)

而不是

this.Invoke(d)

理论上这是表格，所以它应该有效，但如果没有关于例外的更多信息，这是我唯一的猜测。

Answer 2

我放弃......我只是转动轮子而不是......

void listView1_Resize(object sender, EventArgs e)
    {
        listView1.Columns[0].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
        listView1.Columns[1].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
        listView1.Columns[2].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
        listView1.Columns[3].AutoResize(ColumnHeaderAutoResizeStyle.HeaderSize);

    }

Answer 3

//Here ilv is the List, who's column are to be resized
//Get the current column widths
ArrayList widths = new ArrayList();
foreach (ColumnHeader ch in ilv.Columns)
{
    widths.Add(ch.Width);
}

//Get the total width of all the columns
int total_width = 0;
for (int i = 0; i < widths.Count; i++)
{
     total_width += (int)widths[i];
}

//Calculate percentages and resize the columns.
for (int i = 0; i < widths.Count; i++)
{
    double c_width = (int)widths[i];
    double pect = (c_width / total_width);

    //get the new width, leave out 25 pixels for scrollbar
    double n_width = (ilv.Width - 25) * pect;
    n_width = Math.Round(n_width, 0);

    //MessageBox.Show(c_width + " - " + pect + " - " + n_width);
    ilv.Columns[i].Width = (int)n_width;                    
}

Answer 4

你可以这样做：

private void listViewEx_ColumnWidthChanging(object sender, ColumnWidthChangingEventArgs e)
{
    e.Cancel = true;
    e.NewWidth = 60;
}

Answer 5

您可以执行以下代码...

首先获取listview onload的值..

然后将它存储在变量中，在ColumnWidthChanging事件属性中执行此代码，就像这样...

     e.cancel = true;
     e.NewWidth = // the declared variable in which you store the list view with value in the onload function of the form

示例就像这样

    int a = 100;
    e.cancel =true;
    e.e.NewWidth = a;

就像那样

如何以线程安全的方式调整Listview列的大小 - C＃

5 个答案: