Snippet

Protected State Initialization

Readonly fields protect data from being changed after the object is created. This enhances security and prevents accidental bugs in complex logic.

snippet.cs

csharp

public class SecurityToken
{
    // Readonly fields can only be set in the constructor
    public readonly string Value;
 
    public SecurityToken(string secret)
    {
        Value = secret;
    }
 
    public void AttemptChange() 
    {
        // Value = "NewSecret"; // This would cause a compiler error!
    }
}

Breakdown

public readonly string Value;

Declares a field that is immutable once the constructor finishes.

Value = secret;

The only place where this field can be assigned a value.

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Protected State Initialization

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