Page 95 - DCAP312_WEB_TECHNOLOGIES_II

Unit 5: Database Access

//here you can use one of the following Notes
this.dataGrid1.DataSource=dset.Tables[ “customers”];
OR
this.dataGrid1.SetDataBinding(dset, “customers”);
customers: Parent table
orders: Child table
CustomerID in Orders is a foreign key referring to CustomerID primary key in Customers
table.
• If you update the data in the bound DataSet through any mechanism, the DataGrid control
reflects the changes. You can update the data in the DataSet through the DataGrid control,
if the data grid and its table styles and column styles have the ReadOnly property set to
false.
There are four most typical valid data sources for the DataGrid:
• DataTable class

• DataView class
• DataSet class
• DataViewManager class

5.1.4. DataBindings for Textboxes
DataBinding is the ability to bind some elements of a data basis with some graphical elements
of a submission. The data in Windows Form is spring by calling DataBindings. Windows Forms
allow you to bind easily to almost any structure that contains data. Windows Forms Controls
support two types of data binding:
1. Simple Data Binding
2. Complex Data Binding

Simple Data Binding allows you to display a single data element, such as a column value from a
dataset table, in a control. You can simple-bind any property of a control to a data value. Simple
Data Binding can be performed either at design time using DataBindings property of a control
OR dynamically at run time. This is the type of binding typical for controls such as a TextBox
control or Label control that displays typically only a single value.

Simple DataBinding for TextBox “textBox1”
textBox1.DataBindings.Add( “Text”, dataset, “studentTable.studentID”);
The control “textBox1” is bound to the “studentID” column of a table
“studentTable” on the DataSet(dataset) through the BindingContext object.
Complex data binding is the ability of a control to bind to more than one data
element, typically more than one record in a database, or to more than one of
any other type of bindable data element. DataGrid, ListBox and ErrorProvider
controls support Complex data binding.
Here is the method used in this project to bind all TextBoxes:
private void fnGetDataBindingForTextBoxes()
{
this.textboxFirstname.DataBindings .Add( “Text”, datc.dSet.Tables[
“PersonTable”], “FirstName”);

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