Register Default Data Connections

• Dec 24, 2019
• 2 minutes to read

This document describes how to provide a Web Dashboard with a set of data connections. These connections are available in the Dashboard Data Source Wizard when users create new data sources.

To create a data connection, add a connection string to the appsetings.json file or specify a data connection provider:

Add a Connection String to appsettings.json

A connection string should contain the XpoProvider parameter that depends on the database type:

{
    "ConnectionStrings": {
        "MS SQL Connection": "XpoProvider=MSSqlServer; data source=localhost; initial catalog=Northwind; Integrated Security=SSPI; Persist Security Info=True;",
        "XML Connection": "XpoProvider=InMemoryDataStore;Read Only=true;Data Source=Data\\nwind.xml;",
        "JSON Connection to URI": "uri=https://raw.githubusercontent.com/DevExpress-Examples/DataSources/master/JSON/customers.json"
    }
}

See Custom Connection Strings for Data Sources for information on how to specify a custom connection string.

To allow users to create new data sources based on available connection strings, create the DashboardConnectionStringsProvider instance and pass it to the DashboardConfigurator.SetConnectionStringsProvider method:

using DevExpress.DashboardWeb;
// ...
public void ConfigureServices(IServiceCollection services) {
    services
        // ...
        .AddDefaultDashboardController(configurator => {
            configurator.SetConnectionStringsProvider(new DashboardConnectionStringsProvider(Configuration));
        });
    // ...
}

Specify a Data Connection Provider

You can use the DashboardConfigurator.SetConnectionStringsProvider method to specify a data connection provider.

This example shows how to implement a custom connection strings provider by implementing the IDataSourceWizardConnectionStringsProvider interface:

using DevExpress.DataAccess.ConnectionParameters;
using DevExpress.DataAccess.Native;
using DevExpress.DataAccess.Web;
// ...

    public class MyDataSourceWizardConnectionStringsProvider : IDataSourceWizardConnectionStringsProvider {
        public Dictionary<string, string> GetConnectionDescriptions() {
            Dictionary<string, string> connections = new Dictionary<string, string>();

            // Customize the loaded connections list.  
            connections.Remove("LocalSqlServer");
            connections.Add("msSqlConnection", "MS SQL Connection");
            connections.Add("xmlConnection", "XML Connection");
            return connections;
        }

        public DataConnectionParametersBase GetDataConnectionParameters(string name) {
            // Return custom connection parameters for the custom connection.
            if (name == "msSqlConnection") {
                return new MsSqlConnectionParameters("localhost", "Northwind", "", "", MsSqlAuthorizationType.Windows);
            } else if (name == "xmlConnection") {                
                return new XmlFileConnectionParameters("C:\\Users\\Public\\Documents\\DevExpress Demos 18.2\\Components\\Data\\nwind.xml");
            }
            return AppConfigHelper.LoadConnectionParameters(name);
        }
    }

After implementing a custom connection strings provider, pass this class’s instance to the DashboardConfigurator.SetConnectionStringsProvider method:

using DevExpress.DashboardWeb;
// ...
public void ConfigureServices(IServiceCollection services) {
    services
        // ...
        .AddDefaultDashboardController(configurator => {
            configurator.SetConnectionStringsProvider(new MyDataSourceWizardConnectionStringsProvider());
        });
    // ...
}