Command Properties Screen


An explanation of the properties for a command shown on the right side of the screen.

The Command Properties Screen displays properties associated with the currently selected row in the Commands List. The particular properties displayed, and their meaning, depend upon the type of command.

As a special advanced feature, for much of the text displayed through use of the properties, such as titles, choices, and messages, TransForm TPL Templating may be used to insert text computed each time the form is displayed. This templating is done through special expressions enclosed in "{" and "}". Data values are accessible through special names and syntax. See the TPL Templating section for more information. (Note: Early versions of TransForm had a different type of templating which, among other differences, used JavaScript expressions with a different syntax for accessing fields and other data. See the Pre-TPL Syntax section if you are maintaining or upgrading form types that made use of this functionality.)

Some of the common properties shared by more than one command type are listed here.

Command Type 

The first property displays the type of the command. This is not editable. To change the command type you will need to insert a new command and delete the unwanted one.


The comment property is a textbox that lets you enter optional information that will appear in the Commands List. This may be used to leave explanations and other information that may be helpful to a person modifying the Form Type Definition at a later time.

Field Name 

The field property is used to specify particular items in the form instance data that are given values.

In colloquial terms, this is the "name of the field". It is different than the Title of a field, which is what is shown to the person reading or filling out the form. In technical terms, these values specify a particular "attribute/value pair" in the JSON data, giving the attribute name that will appear in the JSON.

These property values correspond to "field names" in a database, but may have hierarchy (a parent-child relationship) as allowed by JSON data and the Data Group functionality. (See the Terminology topic for more information about Form Instance Data JSON and Data Groups.)

In the common case of data fields all at the same level in a hierarchy (that is, no parent-child or one-to-many relationships), you just refer to a field in the data with a simple name in the Field Name property. This is also the case for data fields that are all on the same "level" in a hierarchy.

The name should be made up of letters and numbers and be relatively short (1-30 characters). The name may have meaning if you want (such as "quantityOrdered") or not ("field2"). The name choices may depend upon whether or not you are creating JSON data for use with an existing application. While uppercase and lowercase characters should be considered distinct, it is best to not use names that differ only by case since other applications that read the data may not be case-sensitive with respect to field names.

In general, the field name should not include any characters other than letters and numbers and should not start with a numeric digit. While names with special characters (such as space, "_", or "-") may work for displaying and gathering data on the form (and may be needed when creating or reading JSON for an existing application outside of TransForm) they may cause issues in this app or others reading the data, such as in TPL code.

Names must be unique within a level in the parent-child hierarchy. That is, you may usually use a particular name as a field name for only one field; however, a child field may have the same name. For example: A literal "Parent-Child" form may have a "name" field for the parent, as well as a "name" field in each set of fields for each child.

The Field Name property knows which level it is referring to by the position of the command using it within the Commands List. If the command is within a Data Group, then it refers to the fields within that "sub-array" of the form instance data that correspond to the contents of the Data Group. If the command is at top level (not within a Data Group), then it knows that a Field Name property refers to the top level value in the JSON.


Many of the command types have a layout property. This property helps specify the size and positioning of what is displayed by the command.

In the Command Properties Screen, the layout value will be displayed as a simple text representation of the settings that make up this property. Clicking the value will bring up a list of the current settings that you may then modify by clicking on the appropriate buttons. In many cases the default value will be sufficient.

Some of the settings are checkboxes that toggle on and off. Others are radio buttons that switch between values. Finally, there are "+" and "-" buttons to increment and decrement values, such as the number of columns in a Section. The numeric values may range from 1 to 9.

See Form Layout for more information.

The Preview Screen defaults to showing the Small size (S) layout version of a form type. Use the menu below it to switch to previewing another size.