Null-Conditional Assignment in C# 14 — Elegance Meets Safety

Null-Conditional Assignment in C# 14 — Elegance Meets Safety C# 14 enhances its elegant null-safety tools by allowing null-conditional operators ?. and ?[] to appear on the left-hand side of assignment expressions. This new capability removes repetitive null checks and brings a new level of composability and safety to common mutation patterns in object graphs and collections. In this post, you’ll explore: What is null-conditional assignment What's new in C# 14 Real-world usage examples Supported assignment operations Limitations and best practices The Problem in Pre-C# 14 Before C# 14, you needed explicit null checks before assigning to a property: if (customer is not null) { customer.Order = GetCurrentOrder(); } Or use a ternary: customer?.Order = customer is not null ? GetCurrentOrder() : null; Both approaches were verbose or redundant. The C# 14 Solution Now you can write: customer?.Order = GetCurrentOrder(); This means: ✔️ "Assign only if customer is not null" ✔️ The right-hand side GetCurrentOrder() is not evaluated if customer is null Practical Example Customer-Order Scenario Customer? customer = GetCustomer(); customer?.Order = CreateOrder(); // If customer is not null Dictionary Case with Null-Conditional Indexer Dictionary? scores = GetScores(); scores?["math"] = 95; // Works only if scores is not null Compound Assignments Supported C# 14 allows null-conditional usage with: Operation Example Notes += customer?.Total += 10; Only if customer isn't null -= scores?["math"] -= 5; Only if scores isn't null = data?.Weight = 2; Avoids null exception

May 7, 2025 - 02:09

Null-Conditional Assignment in C# 14 — Elegance Meets Safety

C# 14 enhances its elegant null-safety tools by allowing null-conditional operators ?. and ?[] to appear on the left-hand side of assignment expressions.

This new capability removes repetitive null checks and brings a new level of composability and safety to common mutation patterns in object graphs and collections.

In this post, you’ll explore:

What is null-conditional assignment
What's new in C# 14
Real-world usage examples
Supported assignment operations
Limitations and best practices

The Problem in Pre-C# 14

Before C# 14, you needed explicit null checks before assigning to a property:

if (customer is not null)
{
    customer.Order = GetCurrentOrder();
}

Or use a ternary:

customer?.Order = customer is not null ? GetCurrentOrder() : null;

Both approaches were verbose or redundant.

The C# 14 Solution

Now you can write:

customer?.Order = GetCurrentOrder();

This means:

✔️ "Assign only if customer is not null"

✔️ The right-hand side GetCurrentOrder() is not evaluated if customer is null

Practical Example

Customer-Order Scenario

Customer? customer = GetCustomer();

customer?.Order = CreateOrder(); // If customer is not null

Dictionary Case with Null-Conditional Indexer

Dictionary<string, int>? scores = GetScores();

scores?["math"] = 95; // Works only if scores is not null

Compound Assignments Supported

C# 14 allows null-conditional usage with:

Operation	Example	Notes
`+=`	`customer?.Total += 10;`	Only if `customer` isn't null
`-=`	`scores?["math"] -= 5;`	Only if `scores` isn't null
`*=`	`data?.Weight *= 2;`	Avoids null exception