Set Parameters for Queries in C#

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If a Query has been configured to use Parameters then your C# code can set these parameters before running the query.

This uses the Params LookUp

#todoc - explain how it's configured to use parameters

In a Razor or WebApi file, you would write something like this:

var allPosts = App.Query["AllBlogPosts"];
allPosts.Params("Category", "Web");
var posts = allPosts["Default"];

var dynPosts = AsList(posts);

Warning

Query objects are single use - which is an internal optimization for reliable, rapid access. So if you retrieve various streams, the query still only executes once.
But if you set a parameter after running the query, you will get an error, unless you call Reset() first. See the next example:

var query = App.Query["AllBlogPosts"];
query.Params("Category", "Web");
var webPosts = AsList(query);

// this would result in an error
// allPosts.Params("Category", "IT");

// this works
query.Reset();
query.Params("Category", "IT");
var itPosts = AsList(query);

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History

1. Params was introduced in 2sxc 10.22