DataBind Charts to Excel Data

DataBinding facilitates two-way interaction with data through UI controls. Using the CData ADO.NET Provider for Excel streamlines the process of binding Excel data to Windows Forms and Web controls within Visual Studio. In this article, we will demonstrate using wizards to establish a binding between Excel data and a chart that dynamically updates. Additionally, the code walk-through section will guide you through the creation of a chart using just 10 lines of code.

Binding Data to a Chart

DataBinding to a Chart consists of three steps: Instantiate the control, configure the data source, and databind.

Configure the Connection and Select Database Objects

To create a chart control and establish a connection to Excel, follow the steps outlined below using the Data Source Configuration Wizard. Within the wizard, you'll have the option to choose the specific Excel entities you wish to bind to.

1. In a Windows Forms project, drag and drop a Chart control from the toolbox to the form. In the Data section of the Chart properties, select DataSource and then select Add Project Data Source from the menu. 👁 Add a data source to be bound to the chart.
   
2. In the Data Source Configuration Wizard that appears, select Database -> Dataset.
3. In the Choose Your Data Connection step, click New Connection.

4. In the Add Connection dialog, click Change to select the CData Excel Data Source.

   Below is a typical connection string:

   URI='C:/MyExcelWorkbooks/SampleWorkbook.xlsx';

   Connecting to Local or Cloud-Stored (Box, Google Drive, Amazon S3, SharePoint) Excel Files

   CData Drivers let you work with Excel files stored locally and stored in cloud storage services like Box, Amazon S3, Google Drive, or SharePoint, right where they are.

   Setting connection properties for local files

   Set the URI property to local folder path.

   Setting connection properties for files stored in Amazon S3

   To connect to Excel file(s) within Amazon S3, set the URI property to the URI of the Bucket and Folder where the intended Excel files exist. In addition, at least set these properties:

   • AWSAccessKey: AWS Access Key (username)
   • AWSSecretKey: AWS Secret Key

   Setting connection properties for files stored in Box

   To connect to Excel file(s) within Box, set the URI property to the URI of the folder that includes the intended Excel file(s). Use the OAuth authentication method to connect to Box.

   Dropbox

   To connect to Excel file(s) within Dropbox, set the URI proprerty to the URI of the folder that includes the intended Excel file(s). Use the OAuth authentication method to connect to Dropbox. Either User Account or Service Account can be used to authenticate.

   SharePoint Online (SOAP)

   To connect to Excel file(s) within SharePoint with SOAP Schema, set the URI proprerty to the URI of the document library that includes the intended Excel file. Set User, Password, and StorageBaseURL.

   SharePoint Online REST

   To connect to Excel file(s) within SharePoint with REST Schema, set the URI proprerty to the URI of the document library that includes the intended Excel file. StorageBaseURL is optional. If not set, the driver will use the root drive. OAuth is used to authenticate.

   Google Drive

   To connect to Excel file(s) within Google Drive, set the URI property to the URI of the folder that includes the intended Excel file(s). Use the OAuth authentication method to connect and set InitiateOAuth to GETANDREFRESH.

   When you configure the connection, you may also want to set the Max Rows connection property. This will limit the number of rows returned, which is especially helpful for improving performance when designing reports and visualizations.

   👁 Connection properties for the selected data source in the Add Connection dialog. (Salesforce is shown.)
   
5. Choose the database objects you want to work with. This example uses the Sheet table. 👁 Select database objects. (Salesforce is shown.)
   

DataBind

After adding the data source and selecting database objects, you can bind the objects to the chart. This example assigns the x-axis to Name and the y-axis to Revenue.

1. In the Chart properties, click the button in the Series property to open the Series Collection Editor.
2. In the Series properties, select the columns you want for the x- and y-axes: Select columns from the menu in the XValueMember and YValueMember properties.

The chart is now databound to the Excel data. Run the chart to display the current data. 👁 The chart, filled with data at run time.

Code Walk-through

DataBinding to Excel data requires only a few lines of code and can be completed in three easy steps.

1. Connect to Excel.
2. Create the ExcelDataAdapter to execute the query and create a DataSet to be filled with its results.
3. DataBind the result set to the chart.

Below is the complete code:

ExcelConnection conn = new ExcelConnection("URI='C:/MyExcelWorkbooks/SampleWorkbook.xlsx';");
ExcelCommand comm = new ExcelCommand("SELECT Name, Revenue FROM Sheet", conn);
ExcelDataAdapter da = new ExcelDataAdapter(comm);
DataSet dataset = new DataSet();
da.Fill(dataset);

chart1.DataSource = dataset; 
chart1.Series[0].XValueMember = "Name";
chart1.Series[0].YValueMembers = "Revenue";
// Insert code for additional chart formatting here.
chart1.DataBind();