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# OSLogMessageComponent

The message arguments for a particular entry.

```
class OSLogMessageComponent
```

## Overview

There is one component for each placeholder in the formatString plus one component for any text after the last placeholder.

## Topics

### Reading the Argument

[`argument`](/documentation/OSLog/OSLogMessageComponent/argument-swift.property)

The argument passed into the message component.

[`OSLogMessageComponent.Argument`](/documentation/OSLog/OSLogMessageComponent/Argument-swift.enum)

An object representing data that corresponds to an argument in a message payload.

[`argumentCategory`](/documentation/OSLog/OSLogMessageComponent/argumentCategory-swift.property)

The type of argument that corresponds to the placeholder.

[`OSLogMessageComponent.ArgumentCategory`](/documentation/OSLog/OSLogMessageComponent/ArgumentCategory-swift.enum)

The data type corresponding to the argument provided in a message payload.

### Reading the Message Component

[`formatSubstring`](/documentation/OSLog/OSLogMessageComponent/formatSubstring)

The text immediately preceding a placeholder.

[`placeholder`](/documentation/OSLog/OSLogMessageComponent/placeholder)

The placeholder text for the message component.

### Accessing the Argument

[`argumentDataValue`](/documentation/OSLog/OSLogMessageComponent/argumentDataValue)

The argument formatted as a sequence of bytes.

[`argumentDoubleValue`](/documentation/OSLog/OSLogMessageComponent/argumentDoubleValue)

The argument formatted as a double.

[`argumentInt64Value`](/documentation/OSLog/OSLogMessageComponent/argumentInt64Value)

The argument formatted as a signed 64-bit integer.

[`argumentNumberValue`](/documentation/OSLog/OSLogMessageComponent/argumentNumberValue)

The argument formatted as a number.

[`argumentStringValue`](/documentation/OSLog/OSLogMessageComponent/argumentStringValue)

The argument formatted as a string.

[`argumentUInt64Value`](/documentation/OSLog/OSLogMessageComponent/argumentUInt64Value)

The argument formatted as an unsigned 64-bit integer.


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