Preheat the oven to 350°F (175°C). In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter. Press the mixture into the bottom of the baking pan.

In another bowl, beat the softened cream cheese, sugar, and vanilla extract with an electric mixer until smooth. Add eggs one at a time, mixing well after each addition.

Pour the cheesecake filling over the crust in the baking pan. Bake for 25-30 minutes or until the center is set. Remove from oven and let cool.

In a saucepan, combine strawberries, rhubarb, sugar, cornstarch, and lemon juice. Cook over medium heat until the mixture thickens, about 10 minutes. Let cool.

Spread the strawberry rhubarb topping over the cooled cheesecake. Refrigerate for at least 2 hours before cutting into bars.