Микропроцессорные средства и системы / 4 Вариант / 1_ / 1 лабс АФ / images / survey-library-master / docs / Question / visibleIf

### The list of operators

| Operators | Desciption | Examples |
| ----------------- | ------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------- |
| empty | returns true if the left operand is empty | `{questionName} empty` |
| notempty | returns true if the left operand is not empty | `{questionName} notempty` |
| = == equal | returns true if two values are equal | `{questionName} = 5, {questionName} == 'abc', {questionName} equal 124` |
| <> != notequal | returns true if two values are not equal | `{questionName} <> 5, {questionName} != 'abc', {questionName} notequal 124` |
| > greater | returns true if the left operand greater than the second operand | `{questionName} > 2, {questionName} greater 'a'` |
| < less | returns true if the left operand less than the second operand | `{questionName} < 2, {questionName} less 'a'` |
| >= greaterorequal | returns true if the left operand equal or greater than the second operand | `{questionName} >= 2, {questionName} greaterorequal 'a'` |
| <= lessorequal | returns true if the left operand equal or less than the second operand | `{questionName} <= 2, {questionName} lessorequal 'a'` |
| contains | return true if the left operand is an array and it contains a value of the second operand | `{questionName} contains 'a'` |
| notcontains | return true if the left operand is an array and it does not contain a value of the second operand | `{questionName} notcontains 'a'` |
| ! not | change the result of a condition to the oposite | `!({isLoayl} == 'yes')` |

### Logical operator

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You may use 'or' or '||' or '|' as a logical 'or' operator. The expression returns true if any of two sides return true:
`{questionName1} < 2 || {questionName2} == 'abc'`

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You may use 'and' or '&&' or '&' as a logical 'and' operator. The expression returns true if every of two sides return true:
`{questionName1} < 2 and {questionName2} == 'abc'`

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You may use brackets to build a complex expression:
`{questionName1} < 2 || ({questionName2} == 'abc' and {questionName1} < 5)`

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You may use arithmetic operation as: +, -, _ or / :
`({price} _ {quantity} > 1000)`

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