com.aspose.words

Example:

Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);

builder.write("Statement 1: ");
FieldIf field = (FieldIf)builder.insertField(FieldType.FIELD_IF, true);
field.setLeftExpression("0");
field.setComparisonOperator("=");
field.setRightExpression("1");

// The IF field will display a string from either its "TrueText" attribute,
// or its "FalseText" attribute, depending on the truth of the statement that we have constructed.
field.setTrueText("True");
field.setFalseText("False");
field.update();

// In this case, "0 = 1" is incorrect, so the displayed result will be "False".
Assert.assertEquals(" IF  0 = 1 True False", field.getFieldCode());
Assert.assertEquals(FieldIfComparisonResult.FALSE, field.evaluateCondition());
Assert.assertEquals("False", field.getResult());

builder.write("\nStatement 2: ");
field = (FieldIf)builder.insertField(FieldType.FIELD_IF, true);
field.setLeftExpression("5");
field.setComparisonOperator("=");
field.setRightExpression("2 + 3");
field.setTrueText("True");
field.setFalseText("False");
field.update();

// This time the statement is correct, so the displayed result will be "True".
Assert.assertEquals(" IF  5 = \"2 + 3\" True False", field.getFieldCode());
Assert.assertEquals(FieldIfComparisonResult.TRUE, field.evaluateCondition());
Assert.assertEquals("True", field.getResult());

doc.updateFields();
doc.save(getArtifactsDir() + "Field.IF.docx");