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POPopulating datagridview using asynchronous callback and thread mechanism
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copied!<p>I am new to .NET. I need to complete the following assignment using asynchronous callback mechanism in C# winforms.</p> <p>On a form load I need to get the data from database and populate in a datagridview. The retrieval may take a long time and I want to use the UI meanwhile. Also I need a callback mechanism to check whether datagridview is populated or not. I have to use thread and async callback mechanism to achieve this. </p> <pre><code> private CustomerEntities cn = null; delegate CustomerEntities DataSourceDelegate(); delegate void loadGridViewDelegate(CustomerEntities dtCustomers); DataSourceDelegate delegate_GetCustomers; public CustomerEntities DataSource() { cn = new CustomerEntities(); return cn; } private void Form1_Load(object sender, EventArgs e) { status.Text = "Loading"; delegate_GetCustomers = new DataSourceDelegate(DataSource); delegate_GetCustomers.BeginInvoke(LoadCustomerCallBack, null); } private void LoadCustomerCallBack(IAsyncResult ar) { CustomerEntities dtCutomers; dtCutomers = delegate_GetCustomers.EndInvoke(ar); loadGridView(dtCutomers); } private void loadGridView(CustomerEntities dtCutomers) { if (dataGridView.InvokeRequired) { loadGridViewDelegate del = new loadGridViewDelegate(loadGridView); dataGridView.Invoke(del, new CustomerEntities[] { dtCutomers }); } else { dataGridView.DataSource = dtCutomers.customerDetails; } } </code></pre> <p>The datagridview is getting populated correctly but the UI is blocked when I'm trying to access it when the function is retrieving the data. </p>

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