Pass a Connection String to a Generated DbContext

The default DbContext generated with your Entity Data Model has one constructor that takes no arguments. If you need to build the connection string programatically and pass it to the DbContext, you will have to add your own constructor. However, if you do this in the generated file, {ModelName}.Context.cs, you will lose your changes the next time the {ModelName}.Context.tt script is run.

The solution is to edit the script, {ModelName}.Context.tt. Just add the following code after the code to generate the default constructor (around line 71). Run the script (Ctrl+S), and verify that the new constructor exists in {ModelName}.Context.cs.

    public <#=code.Escape(container)#>(string nameOrConnectionString)
    : base(nameOrConnectionString)
    {
<#
if (!loader.IsLazyLoadingEnabled(container))
{
#>
    this.Configuration.LazyLoadingEnabled = false;
<#
}
#>
    }