Magic Strings
Umbraco Forms has some magic strings that enable you to render values from various sources, such as session, cookies and Umbraco page fields.
Where can I use magic strings?
Magic strings can be used in form fields as a label, description or default value. As an example they can be used in default values in hidden fields - normally in the form of referral codes from a session, cookie or request item.
These values can also be used for properties and settings in workflows. This means you can use name and email fields from a form to create a personal 'Thank you' email.
Sources of magic string values
Request
[@SomeRequestItem] this allows you to display an item from the current HttpContext.Request with the key of 'SomeRequestItem'.
Some examples of variables that are normally available in HttpContext.Request:
[@Url]: Insert the current URL[@Http_Referer]: The previous visited URL (if available)[@Remote_Addr]: The IP address of the visitor (stored by default by Umbraco)[@Http_User_Agent]: The browser of the visitor
The variables are not case-sensitive.
You can use it for any available query string variable in the URL as well. If your URL has the query string ?email=foobar@umbraco.com, you can get the value of the query string into your field by using [@email].
Dictionary Items
For multi-lingual websites, rather than hard-coding labels like form field captions, a dictionary key can be entered as, for example, #MyKey. When the form is rendered, the placeholder will be replaced by the value of the dictionary item identified by the key, according to the current language.
In most cases, the field must contain only the magic string for the replacement to be carried out. This makes sense for translated values, as you will want the whole phrase replaced when, for example, using one for a field's placeholder.
We also translate dictionary keys found within the rich text field, which will be contained within HTML tags. Here we look for dictionary keys making up the full inner text of a tag. So for example, <p>#myKey</p> would be translated, but <p>Lorem ipsum #myKey dolor sit amet.</p> would not.
Session & Cookies
[%SomeSessionOrCookieItem] this allows you to display an item from the current HttpContext.Session with the key of 'SomeSessionOrCookieItem'. The session key can only contain alphanumeric chars and you cannot use dots for example. [%Member.Firstname] cannot be used, but [%MemberFirstname] can be used. You would have to fill these session keys yourself.
If the item cannot be found in the collection of session keys, it will then try to find the item from the HttpContext.Cookies collection with the same key.
Umbraco Page field
[#myUmbracoField] this allows you to insert a property of that page and is based on the alias of the field. If your page has a property with the alias 'title', you can use [#title] in your form.
Some extra variables are:
[#pageName]: The nodename of the current page[#pageID]: The node ID of the current page
Recursive Umbraco Page field
[$myRecursiveItem] this allows you to parse the Umbraco Document Type property myRecursiveItem. So if the current page does not contain a value for this then it will request it from the parent up until the root or until it finds a value.
Additional data
When rendering a form, additional data can be provided in the form of a dictionary. As well as being associated with the created record and available within workflows, they can be used for "magic string" replacements.
They are accessed using this syntax: [+additionalDataKey].
Umbraco Form field
{myAliasForFormField} this allows you to display the entered value for that specific field from the form submission. Used in workflows to send an automated email back to the customer based on the email address submitted in the form. The value here needs to be the alias of the field, and not the name of the field.
Some extra variables are:
{record.id}: The ID of the current record - this is only accessible on workflows triggered "on approve" or "on reject" rather than "on submit"{record.updated}: The updated date/time of the current record{record.created}: The created date/time of the current record{record.umbracopageid}: The Umbraco Page ID the form was submitted on{record.uniqueid}: The unique ID of the current record{record.ip}: The IP address that was used when the form was submitted{record.memberkey}: The member key that was used when the form was submitted
Member properties from a form submission
{member.FOO} with the prefix of member, the same syntax will allow you to retrieve information about the submission if it was submitted by a logged-in member.
Formatting magic strings
Using a magic string such as in the examples above will output the values exactly as read from the source. It's possible to apply a format string to customize the output.
The syntax follows that of AngularJS filters, i.e. [<magic-string> | <formatFunction>: <arg1>: <arg2>].
For example, to truncate a string value read from an Umbraco page field with alias title, you would use:
Umbraco Forms ships with the following filters:
| Filter | Function | Arguments | Example |
|---|---|---|---|
Bound a number |
| min and max bound |
|
Convert string to lower case |
|
| |
Convert string to upper case |
|
| |
Format a number |
| format string |
|
Format a number as a currency |
|
| |
Format a date |
| format string |
|
HTML encode a string |
|
| |
Truncate a string |
| number of characters |
|
The format strings used for formatting dates and numbers are the standard or custom .NET date and numeric format strings respectively.
Further magic string format functions can be created in code for use in forms.
How can I parse these values elsewhere in my C# code or Razor Views?
A service implemented by the IPlaceholderParsingService interface is available for use in custom code or views. It's found in the Umbraco.Forms.Core.Services namespace.
In a controller you can inject it via the constructor and it can also be injected into views via:
The interface implements a single method, ParsePlaceHolders, that can be used for parsing magic strings. There are a few overloads available for use depending on the context.
If parameters for the Record or Form are omitted, magic strings relating to these objects will be removed.
There is also a public extension method ParsePlaceHolders() extending the string object in the Umbraco.Forms.Core.Extensions namespace, again available with some overloads allowing the provision of a Form or Record object if available.
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