Binding Worksheet to a Customized Collection Object using GridWeb
Binding a Worksheet with a Custom Collection
To illustrate this feature, this article goes through how to create a sample application, step by step. First, create a custom collection and then use that collection to binding with a worksheet.
Step 1: Creating a Custom Record
Before creating a custom collection, create a class to hold the custom records that will be stored in the collection. The purpose of this article is to give an idea of how to create your own custom collections and bind them with GridWeb, so how you create the custom record is up to you.
The example below uses the MyCustomRecord class which contains five private fields and five public properties that control access to the private fields. Here is the structure of properties:
- The StringField1 property to read and write stringfield1 (string).
- The ReadonlyField2 property to only read stringfield2 (string).
- The DateField1 property to read and write datefield1 (DateTime).
- The IntField1 property to read and write intfield1 (integer).
- The DoubleField1 property to read and write doublefield1 (double).
C#
//Creating a class that will act as record for the custom collection
public class MyCustomRecord
{
//Private data members
private string stringfield1;
private string stringfield2 = "ABC";
private DateTime datefield1;
private int intfield1;
private double doublefield1;
//Creating a string property
public string StringField1
{
get { return stringfield1; }
set { stringfield1 = value; }
}
//Creating a readonly string property
public string ReadonlyField2
{
get { return stringfield2; }
}
//Creating a DateTime property
public DateTime DateField1
{
get { return datefield1; }
set { datefield1 = value; }
}
//Creating an int property
public int IntField1
{
get { return intfield1; }
set { intfield1 = value; }
}
//Creating a double property
public double DoubleField1
{
get { return doublefield1; }
set { doublefield1 = value; }
}
}
Step 2: Creating a Custom Collection
Now, create a custom collection to add customer records to and access them from. To make it simple, this example uses the MyCollection class which contains a readonly indexer. Using this indexer, we can get any custom record stored in the collection.
C#
//Creating a custom collection
public class MyCollection : CollectionBase
{
//Leaving the collection constructor empty
public MyCollection()
{
}
//Creating a readonly property for custom collection. This Item property is used by GridWeb control to
//determine the collection's type
public MyCustomRecord this[int index]
{
get { return (MyCustomRecord)this.List[index]; }
}
}
Step 3: Binding a Worksheet with a Custom Collection
The process of creating a custom collection is complete. Now use the custom collection to bind to a worksheet in Aspose.Cells.GridWeb . First create a web form, add the GridWeb control to it and add some code.
To use the custom collection for binding, first create an object of the MyCollection class (created in the above step). Then create and add MyCustomRecord objects to the MyCollection object.
Finally, set the MyCollection object as the worksheet’s data source and bind the worksheet with the collection. At this point, you can also create validation rules for the bound columns of the worksheet.
C#
//Implementing Page_Load event handler
protected void Page_Load(object sender, EventArgs e)
{
if (Page.IsPostBack == false && this.GridWeb1.IsPostBack == false)
{
//Creating an object of custom collection
MyCollection list = new MyCollection();
//Creating an instance of Random class
System.Random rand = new System.Random();
//Creating a loop that will run 5 times
for (int i = 0; i < 5; i++)
{
//Creating an object of Custom Record
MyCustomRecord rec = new MyCustomRecord();
//Initializing all properties of Custom Record
rec.DateField1 = DateTime.Now;
rec.DoubleField1 = rand.NextDouble() * 10;
rec.IntField1 = rand.Next(20);
rec.StringField1 = "ABC_" + i;
//Adding Custom Record to Collection
((IList)list).Add(rec);
}
//Accessing a desired worksheet
GridWorksheet sheet = GridWeb1.WorkSheets[0];
//Setting the Data Source of worksheet
sheet.DataSource = list;
//Creating columns automatically
sheet.CreateAutoGenratedColumns();
//Setting the validation type of value to DateTime
sheet.BindColumns[2].Validation.ValidationType = ValidationType.DateTime;
//Binding worksheet
sheet.DataBind();
//Assigning an event handler to InitializeNewBindRow event of the worksheet
//sheet.InitializeNewBindRow += new InitializeNewBindRowHandler(GridWeb1_InitializeNewBindRow);
}
}
Step 4: Handling the Worksheet’s InitializeNewBindRow Event
In the above code, you might have noticed an extra line of code used to assign the GridWeb1_InitializeNewBindRow event handler to the worksheet’s InitializeNewBindRow. This event is triggered whenever a new bound row is added to the worksheet. We created an event handler for this this event because of the MyCustomRecord object’s DateField1 property.
Aspose.Cells.GridWeb automatically initializes int and double values with zero (0) whenever a new bound row is added to the GridWeb control. For dates, we would like the GridWeb control to automatically add the current date from the system. To do so, we have created the GridWeb1_InitializeNewBindRow event handler for the InitializeNewBindRow event.
Access a particular instance of the MyCustomRecord class from the GridWeb using the bindObject argument and then assign the current system date to its DateField1 property.
C#
//Creating GridWeb1_InitializeNewBindRow event handler
private void GridWeb1_InitializeNewBindRow(GridWorksheet sender, object bindObject)
{
//Accessing that custom record object that is newly bound
MyCustomRecord rec = (MyCustomRecord)bindObject;
//Initializing the DateTime of a property when a new row gets bound to the database
rec.DateField1 = DateTime.Now;
}
Step 5: Running the Application
Run the application by either pressing Ctrl+F5 or clicking the Start button in VS.NET. The web form is opened in a new browser window.
Worksheet bound with a custom collection
Right-click the GridWeb control to add or delete a record. For example, add a new record to the worksheet by selecting Add Row option.
Selecting Add Row option from the menu
When a new row is added to the worksheet, cells contain default data including the current system date.
New row added to worksheet with default data
After making changes to the data, click Save or Submit to save your changes.
Saving changes by clicking Save button
