Google Column Chart

please explain me how to devolope Google column chart from the gridview

alearedy i did colum chart with the help of This Link https://www.youtube.com/watch?v=S1znB1LDlK4

And its my code

[WebMethod]

[ScriptMethod(ResponseFormat = ResponseFormat.Json)]

public static object[] GetChartData()

{

List data = new List();

//Here MyDatabaseEntities is our dbContext

using (EonsEntities dc = new EonsEntities())

{

data = dc.GOOGLECHARTDATAs.ToList();

}

var chartData = new object[data.Count + 1];

chartData[0] = new object[]{

"Year",

"Electronics",

"Books & Media",

"Home & Kitchen"

};

int j = 0;

foreach (var i in data)

{

j++;

chartData[j] = new object[] { i.YEAR.ToString(), i.ELECTRONICS, i.BOOKANDMEDIA, i.HOMEANDKITCHEN };

}

return chartData;

}

But I need Generate Bar from Gridview