How to Bind GridView with Class instead of DataTable

You have seen many times that the GridView is bind with DataTable and wonder if you can bind it by another way. The answer is "Yes", you can bind a GridView with a Class too.

Bind GridView with Class

Let me show you how to bind your GridView using a Class.

1. First add the GridView to the Web Form.

<asp:GridView ID="gridView" runat="server"></asp:GridView>

2. Go to the CS page and create a Product Class.

class Product
    {
        public string name { get; set; }
        public string image { get; set; }
        public string categoryName { get; set; }
        public decimal price { get; set; }
    }

3. Create a function that fills the Class with dummy data.

void LoadData()
    {
        product = new List<Product>();
        product.Add(new Product() { name = "Vanheusen Women's Skirt", image = "Image/s1.jpg", categoryName = "Skirts", price = 20.89M });
        product.Add(new Product() { name = "Decot Paradise Animal Print Women's Regular Black Skirt", image = "Image/s2.jpg", categoryName = "Skirts", price = 35.59M });
        product.Add(new Product() { name = "DeeVineeTi Polka Print Women's Wrap Around White, Blue Skirt", image = "Image/s3.jpg", categoryName = "Skirts", price = 98.00M });
        product.Add(new Product() { name = "Raabta Fashion Striped Women's Pencil Black, White Skirt", image = "Image/s4.jpg", categoryName = "Skirts", price = 120.00M });
        product.Add(new Product() { name = "Ishin Solid Women's Regular Orange Skirt", image = "Image/s5.jpg", categoryName = "Skirts", price = 115.85M });
        product.Add(new Product() { name = "Adidas Women's Skirt", image = "Image/s6.jpg", categoryName = "Skirts", price = 105.74M });

        product.Add(new Product() { name = "V Dot by Van Huesen Skinny Fit Men's Grey Trousers", image = "Image/p1.jpg", categoryName = "Pants", price = 10.89M });
        product.Add(new Product() { name = "French Connection Slim Fit Men's Beige Trousers", image = "Image/p2.jpg", categoryName = "Pants", price = 25.59M });
        product.Add(new Product() { name = "Indian Terrain Slim Fit Men's White Trousers", image = "Image/p3.jpg", categoryName = "Pants", price = 48.00M });
        product.Add(new Product() { name = "United Colors of Benetton Slim Fit Men's Beige Trousers", image = "Image/p4.jpg", categoryName = "Pants", price = 120.00M });
        product.Add(new Product() { name = "Numero Uno Slim Fit Men's Black Trousers", image = "Image/p5.jpg", categoryName = "Pants", price = 155.85M });
        product.Add(new Product() { name = "John Players Slim Fit Men's Grey Trousers", image = "Image/p6.jpg", categoryName = "Pants", price = 165.74M });

        product.Add(new Product() { name = "Vu 140cm (55) Full HD Smart LED TV", image = "Image/e1.png", categoryName = "Electronics", price = 80.89M });
        product.Add(new Product() { name = "BPL Vivid 80cm (32) HD Ready LED TV", image = "Image/e2.png", categoryName = "Electronics", price = 235.59M });
        product.Add(new Product() { name = "Moto E3 Power (Black, 16 GB)", image = "Image/e3.jpg", categoryName = "Electronics", price = 198.00M });
        product.Add(new Product() { name = "Krishna M (Silver, 64 GB)", image = "Image/e4.jpg", categoryName = "Electronics", price = 120.00M });
        product.Add(new Product() { name = "Sansui 150 L Direct Cool Single Door Refrigerator", image = "Image/e5.jpg", categoryName = "Electronics", price = 115.85M });
        product.Add(new Product() { name = "Whirlpool 245 L Frost Free Double Door Refrigerator", image = "Image/e6.jpg", categoryName = "Electronics", price = 105.74M });
    }

4. Fill the class with data.

LoadData();

5. Now finally bind the GridView with the class data like this:

gridView.DataSource = product;
gridView.DataBind();


Binding GridView with Class on Page Load Event
Here I will show you how to bind the GridView on Page Load event.

Add the below code to the .cs page.

List<Product> product;
protected void Page_Load(object sender, EventArgs e)
{
    if(!IsPostBack)
    {
        LoadData();
        gridView.DataSource = product;
        gridView.DataBind();
    }
}

void LoadData()
{
    //code
}

class Product
{
    public string name { get; set; }
    public string image { get; set; }
    public string categoryName { get; set; }
    public decimal price { get; set; }
}

and that's it the Binding of GridView is done.

Related Article: Also check the related article which teaches the 'Binding of GridView with Paging using jQuery Load with No Page Refresh'. Check this article here - asp.net gridview example.

Preventing Phantom Reads in SQL Server using Locks

In multi user systems, when a user is allowed to read data from a row that has been modified by another user and not yet committed, is known as Phantom Reads.

For example – I have a Students table that contains Students record. I update the student name, with id 5, from ‘Mila’ to ‘Maria’. But before it is committed, another user reads the student with id 5. The other user will get ‘Mila’ for the name but actually the ‘Mila’ is changed to ‘Maria’ and so it becomes Phantom Read (i.e. a non-existent record or phantom).

How to Prevent Phantom Reads

During the time of insert, update or delete work on the table, the SQL Server will automatically place the table under lock. So it will automatically prevent Phantom Reads.

But if one user removes the lock (for faster execution of query) then Phantom reads can happen

Note - Removing the lock can be done with this statement - with(nolock)

Suppose there are 2 users and both of them executes some SQL Statement.

Note - The second user executes the statement after 1 second.

First User executes:

begin tran

update Student set name='Maria' where ID=5

waitfor delay '00:00:15'

rollback     

Second User executes (after 1 second):

select name from Student with(nolock) where ID=5 

Here you can see that the first user changes the student name from ‘Mila’ to ‘Maria’ then after a delay of 15 seconds rolls back it to ‘Mila’.

The second, who executes the SQL statement by relaxing the lock will read the name as ‘Maria’. 

The name ‘Maria’ is a Phantom (non-existant) since first user has reverted back to ‘Mila’

Note – The relaxation of lock can be used for faster execution of Queries in some situations. But I would not recommend using them when doing CRUD Operations in SQL Server.

You can run both the users statements in separate query window to see the result they give to you.

If the second user does not use with(nolock) then SQL Server will make him wait for 15 seconds till the lock gets removed and then gives him ‘Mila’ for the student with id 5.