# `GSInstance customBoolValueForKey:defaultValue:`

*Instance Method*

Returns the boolean value of the custom parameter for the specified key, or the default value if not found.

## Declaration

```swift
func customBoolValue(forKey key: String, defaultValue: Bool) -> Bool
```

```objc
- (BOOL) customBoolValueForKey:(NSString *) key defaultValue:(BOOL) defaultValue;
```

```python
customBoolValueForKey_defaultValue_(key: str, defaultValue: bool) -> bool
```

## Parameters

- `key` — The key.
- `defaultValue` — The default value.

## Return Value

The boolean value of the custom parameter, or the default value.