# Set Field Value Action

A set field action requires the selection of a form field and a "value" that will be set into the field.  The "value" can be either:

* A specific value that may be a number, some text, true/false, etc.
* An expression that combines specific values and/or fields using arithmetic/text/logic operators and optionally parenthesis.

To support the above possibilities, set field actions support both a value entry "mode" and an expression entry "mode".  Set field actions will always start in value entry mode.  In value entry mode you may simply enter a number or text or if the field is a select type field, select one of the select options.  

<figure><img src="/files/uA3manzHsG3DAv6DW3CZ" alt=""><figcaption></figcaption></figure>

The set field actions have an overflow menu (3-dot icon) that has an option to put the input into expression input mode (see above).  In expression input mode, enter specific values and/or select fields and combine them with operators and parenthesis as needed.

Here are some very simple examples:

<figure><img src="/files/sdXxDTDOMygcnDFOju5X" alt=""><figcaption><p>Example Rule Builder numeric expression</p></figcaption></figure>

<figure><img src="/files/87G8djKH4SeNJw9cP4tl" alt=""><figcaption><p>Example Rule Builder Expression combining text</p></figcaption></figure>

## Expression Operators

The following operators are supported in expressions.  Parenthesis are also supported for numeric expressions.

| Operator | Name                  | Purpose                                               | Example                    |
| -------- | --------------------- | ----------------------------------------------------- | -------------------------- |
| +        | Addition              | Add two numeric sub-expressions                       | a + b                      |
| -        | Subtraction           | Subtract two numeric sub-expressions                  | a - b                      |
| \*       | Multiplication        | Multiply two numeric sub-expressions                  | a \* b                     |
| /        | Division              | Divide two numeric sub-expressions                    | a / b                      |
| +        | Concatenation         | Concatenate two text sub-expressions                  | firstName + " " + lastName |
| ==, ===  | Equality              | Compare two sub-expressions for equality              | a == b                     |
| !=, !==  | Inequality            | Compare two sub-expressions for inequality            | a !== b                    |
| >        | Greater than          | Compare two sub-expressions for greater than          | a > b                      |
| >=       | Greater than or equal | Compare two sub-expressions for greater than or equal | a >= b                     |
| <        | Less than             | Compare two sub-expressions for less than             | a < b                      |
| <=       | Less than or equal    | Compare two sub-expressions for less than or equal    | a <= b                     |


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