ContainsField

ContainsField( field, in )
ContainsField( field, in )
ContainsField( field, in )
ContainsField( field, in )
contains_field( field, in )
ContainsField( field, in )

Description

The ContainsField function returns true if the specified field exists within the result of the in expression, or false otherwise.

ContainsField is useful when you need to distinguish between objects, arrays, or documents that contain a field and those that do not.

Parameters

Argument Type Definition and Requirements

field

types:string[]

The name of a field.

in

Any

A value of any type.

Returns

A boolean value indicates whether field exists within in.

Examples

The following query returns true because the field a exists in the provided object:

try
{
    Value result = await client.Query(
        ContainsField(
            "a",
            Obj(
                "a", 1,
                "b", 2,
                "c", 3
            )
        )
    );

    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
BooleanV(True)
result, err := client.Query(
	f.ContainsField(
		"a",
		f.Obj{
			"a": 1,
			"b": 2,
			"c": 3 }))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}
true
System.out.println(
    client.query(
        ContainsField(
            Value("a"),
            Obj(
                "a", Value(1),
                "b", Value(2),
                "c", Value(3)
            )
        )
    )
    .get());
true
client.query(
  q.ContainsField(
    'a',
    {
      'a': 1,
      'b': 2,
      'c': 3,
    },
  )
)
.then((ret) => console.log(ret))
.catch((err) => console.error('Error: %s', err))
true
result = client.query(
  q.contains_field(
    "a",
    {
      "a": 1,
      "b": 2,
      "c": 3
    }
  )
)
print(result)
True
try {
  println(Await.result(
    client.query(
        ContainsField(
            "a",
            Obj(
                "a" -> 1,
                "b" -> 2,
                "c" -> 3
            )
        )
    ),
    5.seconds
))} catch {
  case unknown: Throwable => println("Error: " + unknown.getMessage())
}
true

The following query returns false because the field f does not exist in the provided object:

try
{
    Value result = await client.Query(
        ContainsField(
            "f",
            Obj(
                "a", 1,
                "b", 2,
                "c", 3
            )
        )
    );

    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
BooleanV(False)
result, err := client.Query(
	f.ContainsField(
		"f",
		f.Obj{
			"a": 1,
			"b": 2,
			"c": 3 }))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}
false
System.out.println(
    client.query(
        ContainsField(
            Value("f"),
            Obj(
                "a", Value(1),
                "b", Value(2),
                "c", Value(3)
            )
        )
    )
    .get());
false
client.query(
  q.ContainsField(
    'f',
    {
      'a': 1,
      'b': 2,
      'c': 3,
    },
  )
)
.then((ret) => console.log(ret))
.catch((err) => console.error('Error: %s', err))
false
result = client.query(
  q.contains_field(
    "f",
    {
      "a": 1,
      "b": 2,
      "c": 3
    }
  )
)
print(result)
False
try {
  println(Await.result(
    client.query(
        ContainsField(
            "f",
            Obj(
                "a" -> 1,
                "b" -> 2,
                "c" -> 3
            )
        )
    ),
    5.seconds
))} catch {
  case unknown: Throwable => println("Error: " + unknown.getMessage())
}
false

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