We can use PowerShell to discover many SSRS properties, including the different parameters available in a report. This blog post is based on SQL Server 2014 and PowerShell V5.
Here is an example:
This particular report utilizes different variations of parameters. To review, here are the available data types for SSRS report parameters:
In the example above, Customer ID is an integer. Order Date From and To are dates. Online Flag is a boolean. Min Total Due is a float. Status is a multi-value text.