Ticket custom fields allow users to add extra information to a ticket.  To create ticket custom fields, please follow the steps below:

Go to Home Page>>Click on Admin icon>>Ticket Custom fields
 

Click on  Add in the Ticket custom fields section of the page. Enter the details. Fields marked with Asterisk (*) symbol are mandatory and have to be filled.

Fields defined below: 

Field Name:  Name of the Ticket Custom Field.
Label: The display label for this field.  
Help Text: Giving out more descriptions about the label field name. Shown to the user when editing the ticket. 
Parent id: Define custom field only based on some field. For example, if you want to create State as a custom field for a ticket, so here Parent id will be State and Parent value will be - the name of the states (Karnataka, Mumbai, etc).  Parent value can be listed in the List Values field.
Parent Field Value: Parent value depends on the Parent id. Populates the custom field for the mentioned parent field value.
Data: Select the Data types as per your needs.  

Note-List & Multiselect has to be pre-defined, it cannot be populated by the user.  For example: For the Parent ID- State. please list out the names of the states, so that users can select the states from the available list. In Multiselect, the user has the provision to select more than one option from the list.

Maximum Length (characters): Defines the length of the character. If length is defined as 10, then the user cannot enter more than 10 characters. But incase if the user does not want to set a limit for the characters then the field can be left blank.

Decimal Places: Only used for decimal fields:- Defines how many decimals are allowed
Add empty first choice to List? :  Check the box if you want to add an empty dropdown. For example- if you define a list where the user enters yes or no.  But in some cases, the user would prefer to keep the field empty. It would be neither yes nor no. but an empty dropdown.  Applicable for data type- List: adds an empty first entry to the choices list.
List Values: For list fields only. Enter one option per line.
Ordering:  Defines Order of the form,  which field has to come first Lower numbers are displayed first; higher numbers are listed later
Queues: Select those queues you wish to limit this field to. Hold down "Control", or "Command" on a Mac, to select more than one.
Required? Does the user have to enter a value for this field?- Adding information to custom fields can be made optional or required. Uncheck the box if not required.  If this box is checked. it will be a required field. the user has to enter the value for this field before sending the form.   
Staff Only? If this is ticked, then the public submission form will NOT show this field- Can keep it unchecked.

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