## FieldIf class

Implements the IF field.
To learn more, visit the [Working with Fields](https://docs.aspose.com/words/python-net/working-with-fields/) documentation article.




### Remarks

Compares the values designated by the expressions [FieldIf.left_expression](./left_expression/) and [FieldIf.right_expression](./right_expression/)
in comparison using the operator designated by [FieldIf.comparison_operator](./comparison_operator/).

A field in the following format will be used as a mail merge source: { IF 0 = 0 "{PatientsNameFML}" "" \\\* MERGEFORMAT }




**Inheritance:** [FieldIf](./) → [Field](../field/)

### Constructors
| Name | Description |
| --- | --- |
| [FieldIf()](./__init__/#default) | The default constructor. |

### Properties

| Name | Description |
| --- | --- |
| [comparison_operator](./comparison_operator/) | Gets or sets the comparison operator. |
| [display_result](../field/display_result/) | Gets the text that represents the displayed field result.<br>(Inherited from [Field](../field/)) |
| [end](../field/end/) | Gets the node that represents the field end.<br>(Inherited from [Field](../field/)) |
| [false_text](./false_text/) | Gets or sets the text displayed if the comparison expression is ``False``. |
| [format](../field/format/) | Gets a [FieldFormat](../fieldformat/) object that provides typed access to field's formatting.<br>(Inherited from [Field](../field/)) |
| [is_dirty](../field/is_dirty/) | Gets or sets whether the current result of the field is no longer correct (stale) due to other modifications made to the document.<br>(Inherited from [Field](../field/)) |
| [is_locked](../field/is_locked/) | Gets or sets whether the field is locked (should not recalculate its result).<br>(Inherited from [Field](../field/)) |
| [left_expression](./left_expression/) | Gets or sets the left part of the comparison expression. |
| [locale_id](../field/locale_id/) | Gets or sets the LCID of the field.<br>(Inherited from [Field](../field/)) |
| [result](../field/result/) | Gets or sets text that is between the field separator and field end.<br>(Inherited from [Field](../field/)) |
| [right_expression](./right_expression/) | Gets or sets the right part of the comparison expression. |
| [separator](../field/separator/) | Gets the node that represents the field separator. Can be ``None``.<br>(Inherited from [Field](../field/)) |
| [start](../field/start/) | Gets the node that represents the start of the field.<br>(Inherited from [Field](../field/)) |
| [true_text](./true_text/) | Gets or sets the text displayed if the comparison expression is true. |
| [type](../field/type/) | Gets the Microsoft Word field type.<br>(Inherited from [Field](../field/)) |

### Methods

| Name | Description |
| --- | --- |
|[ evaluate_condition()](./evaluate_condition/#default) | Evaluates the condition. |
|[ get_field_code()](../field/get_field_code/#default) | Returns text between field start and field separator (or field end if there is no separator). Both field code and field result of child fields are included.<br>(Inherited from [Field](../field/)) |
|[ get_field_code(include_child_field_codes)](../field/get_field_code/#bool) | Returns text between field start and field separator (or field end if there is no separator).<br>(Inherited from [Field](../field/)) |
|[ remove()](../field/remove/#default) | Removes the field from the document. Returns a node right after the field. If the field's end is the last child of its parent node, returns its parent paragraph. If the field is already removed, returns ``None``.<br>(Inherited from [Field](../field/)) |
|[ unlink()](../field/unlink/#default) | Performs the field unlink.<br>(Inherited from [Field](../field/)) |
|[ update()](../field/update/#default) | Performs the field update. Throws if the field is being updated already.<br>(Inherited from [Field](../field/)) |
|[ update(ignore_merge_format)](../field/update/#bool) | Performs a field update. Throws if the field is being updated already.<br>(Inherited from [Field](../field/)) |

### Examples

Shows how to insert an IF field.

```python
doc = aw.Document()
builder = aw.DocumentBuilder(doc=doc)
builder.write('Statement 1: ')
field = builder.insert_field(field_type=aw.fields.FieldType.FIELD_IF, update_field=True).as_field_if()
field.left_expression = '0'
field.comparison_operator = '='
field.right_expression = '1'
# The IF field will display a string from either its "TrueText" property,
# or its "FalseText" property, depending on the truth of the statement that we have constructed.
field.true_text = 'True'
field.false_text = 'False'
field.update()
# In this case, "0 = 1" is incorrect, so the displayed result will be "False".
self.assertEqual(' IF  0 = 1 True False', field.get_field_code())
self.assertEqual(aw.fields.FieldIfComparisonResult.FALSE, field.evaluate_condition())
self.assertEqual('False', field.result)
builder.write('\nStatement 2: ')
field = builder.insert_field(field_type=aw.fields.FieldType.FIELD_IF, update_field=True).as_field_if()
field.left_expression = '5'
field.comparison_operator = '='
field.right_expression = '2 + 3'
field.true_text = 'True'
field.false_text = 'False'
field.update()
# This time the statement is correct, so the displayed result will be "True".
self.assertEqual(' IF  5 = "2 + 3" True False', field.get_field_code())
self.assertEqual(aw.fields.FieldIfComparisonResult.TRUE, field.evaluate_condition())
self.assertEqual('True', field.result)
doc.update_fields()
doc.save(file_name=ARTIFACTS_DIR + 'Field.IF.docx')
```

### See Also

* module [aspose.words.fields](../)
* class [Field](../field/)