C＃.Net中的线程安全网格视图更新

Question

I am explaining my problem elaborately. I have a dataGridView in Windows main form. I have a timer which is starting when button1 is clicked. and it stops when button2 is clicked.

Now in the meantime I am calculating something and putting it in the dataGridView . This is a dynamic calculation. In this calculation I am using a Thread. (I am absolutely new in Threads) . I have used Thread.Sleep(100) to calculate data. Now I am using a Thread.Sleep in a loop where I am calculating data of consecutive things. I want the respective order of the calculation to remain. After each iteration of the loop I am using dataGridView.Rows.AddRange(DataGridViewRow) to add new row with new data calculated.

But I am not getting the data in the dataGridView in the order and also it's not coming properly. It's getting blanked out sometime and coming randomly.

PS - I am clearing the data each time when the timer interval is over.

Answer 1

You can only access UI controls from the UI thread.

If you try to access them from other threads, you get undefined behavior as you have found.

I suggest you start by reading this free ebook: Albahari

Answer 2

Before you attempt to update the datagridview, you need to call datagridview.InvokeRequired. If this is true then, call Invoke passing in the delegate which you wish to execute and any data that you want to pass.

Answer 3

It has been resolved. Actually you have to set the Thread.Sleep timer such that it gets completed before your Windows.Forms.Timer 's interval is over.

Answer 4

Here is the thread safe method to set Gridview.

class Program
{
public static List<string> ChoiceExtension = new List<string>();
static void Main()
{
    ChoiceExtension.Add("One");
    ChoiceExtension.Add("Two");
    ChoiceExtension.Add("Three");
    //Set list as gridsource
    InserttoGrid(ChoiceExtension);

}

public static void SetDataSource(object value)
    {
        DataTable dt = new DataTable();
        dt.Columns.Add("Path of Extension");
        foreach (var item in value as List<string>)
        {
            dt.Rows.Add(new object[] { item });

        }
        ExtensionList.DataSource = dt;
    }
public static void InserttoGrid(List<string> List)
    {
        if (ChoiceExtension.Count >0)
        {

            if (this.ExtensionList.InvokeRequired)
            {
               ExtensionList.Invoke(new SetDataSourceDelegate(SetDataSource), new Object[] { List });


            }
            else
            {
                SetDataSource(List);

            }

        }
    }

}