---
source_files:
  - Common/DTS.Common/Classes/DTS.Viewer/Commands/RelayCommand.cs
generated_at: "2026-04-17T16:40:01.838480+00:00"
model: "zai-org/GLM-5-FP8"
schema_version: 1
sha256: "24962272b11a45e1"
---

# Commands

## Documentation: `DTS.Common.Classes.Viewer.Commands.RelayCommand`

### 1. Purpose
This module provides an implementation of the `System.Windows.Input.ICommand` interface designed to delegate logic to methods passed as parameters. It exists to support the MVVM (Model-View-ViewModel) pattern within the DTS Viewer application, allowing UI controls (like buttons) to bind to actions defined in ViewModels without requiring the creation of separate concrete command classes for every action.

### 2. Public Interface

**Constructors**

*   `public RelayCommand(Action<object> execute)`
    *   Initializes a new instance of the `RelayCommand` class that can always execute.
    *   **Parameter:** `execute` — The execution logic delegate.
    *   **Behavior:** Calls the overloaded constructor with `null` for the `canExecute` predicate.

*   `public RelayCommand(Action<object> execute, Predicate<object> canExecute)`
    *   Initializes a new instance of the `RelayCommand` class.
    *   **Parameters:**
        *   `execute` — The execution logic delegate.
        *   `canExecute` — The execution status logic delegate (optional).
    *   **Behavior:** Throws an `ArgumentNullException` named "execute" if the `execute` delegate is null. Assigns delegates to internal readonly fields.

**Methods**

*   `public bool CanExecute(object parameter)`
    *   Determines if the command can execute in its current state.
    *   **Behavior:** Returns `true` if `_canExecute` is `null`. Otherwise, returns the result of invoking `_canExecute(parameter)`