# The Expression editor

To create an expression, type it directly in the Tag or expression box in the editor you are working in, or click the Browse button (…) to open the Expression editor and use the editor to create one.

These buttons in the Expression editor each provide a list of operators for use in expressions:

- If
- Logical
- Relational
- Arithmetic
- Bitwise

The editor also contains these buttons:

- Functions button - opens a dialog box with access to all the functions that can be used in expressions.
- Tags button - opens the Tag Browser to let you search the database for a particular tag.
- Check Syntax button - checks that the expression entered uses valid syntax. If there are any errors, they are listed in the box next to the button. If there are no errors, Valid is shown in the box. If you make changes to the expression, check the syntax again.

  The application does not check the syntax of expressions you type in the Tag or Expression box.

- The Line and Column boxes show the cursor position in the Expression box.

## To create an expression using the Expression editor

1. Type the expression in the Expression box, up to 999 characters long.
2. Use the buttons to enter the operators or functions you need in the edit box.
3. Use the Tags button to open the Tag Browser, where you can choose tags for the expression.
4. Click the Check Syntax button to check for syntax errors.
5. Click OK when the expression is complete.

## To select an operator

1. Click the button for the operators you want to list.
2. Click an operator to copy it to the expression edit box.

## To select a function

1. Click the Functions button to show the alphabetical listing of the functions available.
2. Highlight the function you want, then click OK. Or, double-click the function.

   This copies the function to the Expression edit box.

   Tip: | Press Ctrl-Tab to insert a tab in the expression. You can cut, copy and paste expressions or parts of expressions between objects and editors.

## See also

About expressions

Formatting expressions

Add comments to expressions

Causes of run-time errors for expressions

Select functions

The Tag Browser