Creating and Modifying Counters

  • Use the CountersFor.Increment method to create a new Counter or modify an existing Counter's value.

  • If the Counter exists, Increment will add a number to the Counter's current value.
    If the Counter doesn't exist, Increment will create it and set its initial value.

  • In this page:

Increment Syntax

void Increment(string counterName, long incrementValue = 1);
Parameters Type Description
counterName string Counter's name
incrementValue long Increase Counter by this value. Default value is 1.
For a new Counter, this will be its initial value.

Increment Usage

  • Flow:

    • Open a session
    • Create an instance of CountersFor.
    • Execute CountersFor.Increment
    • Execute session.SaveChanges for the changes to take effect
  • Note:

    • Modifying a Counter using Increment only takes effect when session.SaveChanges() is executed.
    • To decrease a Counter's value, pass the method a negative number to Increment.

Code Sample

// 1. Open a session
using (var session = docStore.OpenSession())
    // 2. pass CountersFor's constructor a document ID  
    var documentCounters = session.CountersFor("products/1-C");

    // 3. Use `CountersFor.Increment`
    documentCounters.Increment("ProductLikes"); // Increase "ProductLikes" by 1, or create it with a value of 1
    documentCounters.Increment("ProductDislikes", 1); // Increase "ProductDislikes" by 1, or create it with a value of 1
    documentCounters.Increment("ProductPageViews", 15); // Increase "ProductPageViews" by 15, or create it with a value of 15
    documentCounters.Increment("DaysLeftForSale", -10); // Decrease "DaysLeftForSale" by 10, or create it with a value of -10

    // 4. Save changes to the session