Populate Gridview at runtime using textfile

Question

it may seem to be simple problem to many of you, but want i am trying to do is i am reading a text file on a click event using StreamReader (ASP.net & C#) after

Answer 1

How about something like this:

    protected void readfile_Click(object sender, EventArgs e)
    {
        DataTable table = new DataTable();
        table.Columns.Add("Row No.");
        table.Columns.Add("Col No.");
        table.Columns.Add("Width");
        table.Columns.Add("Height");
        table.Columns.Add("Image URL");
        table.Columns.Add("Description");

        using (StreamReader sr = new StreamReader(@"D:\Temp\fileread\readtext.txt"))
        {
            while (!sr.EndOfStream)
            {
                string[] parts = sr.ReadLine().Split(',');
                table.Rows.Add(parts[0], parts[1], parts[2], parts[3], parts[4], parts[5]);
            }
        }
        MyGridView.DataSource = table;
        MyGridView.DataBind();
    }

Answer 2

Add columns to datatable using code below

DataTable dt = new DataTable();
dt.Columns.Add("Row No", typeof(Int32));
dt.Columns.Add("Col No", typeof(Int32));
dt.Columns.Add("Width", typeof(Int32));
dt.Columns.Add("Height", typeof(Int32));
dt.Columns.Add("ImageUrl", typeof(String));
dt.Columns.Add("Description", typeof(String));

And bind datatable (dt) after you populate all rows in datatable, after while loop

using (StreamReader sr = new StreamReader(@"D:\Temp\fileread\readtext.txt"))
{
    while ((line = sr.ReadLine()) != null)
    {
        string[] parts = line.Split(',');
        var dr = dt.NewRow(); //use newrow to create new row
        for (int i = 0; i < parts.Length; i++)
        {
            dr[i] = parts[i];
        }
        
        dt.Rows.Add(dr); //add row to datatable now
    }
    sr.Close();
}
//bind datatable to Gridview after we load file into dt
MyGridView.DataSource = dt;
MyGridView.DataBind();

Answer 3

1. You should move your code with adding the DataColumn outside the for-loop
2. You should create new DataRow using DataTable.NewRow method
3. You should call data binding methods only once, and after the loops.

Your code should be something like this:

DataTable dt = new DataTable();
dt.Columns.Add("Row No", typeof(Int32));
dt.Columns.Add("Col No", typeof(Int32));
dt.Columns.Add("Width", typeof(Int32));
dt.Columns.Add("Height", typeof(Int32));
dt.Columns.Add("ImageUrl", typeof(String));
dt.Columns.Add("Description", typeof(String));

using (StreamReader sr = new StreamReader(@"D:\Temp\fileread\readtext.txt"))
{
    while ((line = sr.ReadLine()) != null)
    {
        string[] parts = line.Split(',');
        var row = dt.NewRow();
        for (int i = 0; i < parts.Length; i++)
        {
            row[i] = parts[i];
        }
        // important thing!
        dt.Rows.Add(row);
    }
    sr.Close();
}
MyGridView.DataSource = dt;
MyGridView.DataBind();