# String.match

## Function

Returns a string or regular expression match result.

## Syntax

```bt
string.match(pattern)
```

## Parameters

| Parameters | Type | Required | Default value | Description |
| ------ | ------ | ------ | ------ | ------ |
| pattern | String/Regex | No | '' | The string or regular expression to match. |

## Return value

| Type | Description |
| ------ | ------ |
| Array/Empty | If string pattern matching is successful, an array containing needle will be returned; if the regular pattern does not have the g flag, a capture group array will be returned; if the regular pattern has the g flag, all matching text will be returned; if there is no match, Empty will be returned. |

## Example

```bt
text = 'hello BT'
result = text.match('BT')

// Output: ["BT"]
print result
```

## Notes

- When there is no g flag in the regular expression, the 0th item is a complete match, and subsequent items are capturing groups; the missing capturing group is Null.