====== Read Cookie (Expression Function) ======

===== Purpose =====
The **Read Cookie** function (READ_COOKIE) reads a cookie from the browser that was set using a [[Action Type - Set Browser Cookie|Set Browser Cookie]] [[Action|action]].  It is commonly used to track a user to determine if he or she has accessed a page before.  It is **not** advisable to use cookies for important security checks because it is easy for a cookie to be deleted, added, or copied which could lead to a security breach.

{{ :read_cookie_initial.png?nolink |}}
===== Parameters =====
The **Read Cookie** function has one required parameter:

==== Cookie Name ====

Allowed Inputs: [[Field|field]] value or text string

Either use the use the [[Query Builder]] to choose a field that contains the name of the cookie or use type a value to enter a text string that is the name of the cookie.

===== Output =====

The output of the **Read Cookie** function is a string that was previously set by the set browser cookie action.  If the cookie does not exist then an empty string will be returned.

===== Example =====

The output of the **Read Cookie** function is based on the value set by the action.  For example if a set browser cookie action set the value "Bobby" to the cookie titled "Nickname" then READ_COOKIE("Nickname") would return "Bobby".