This post provides a handy reference guide to go from Scratch’s “Operators” category of code blocks to C# with Unity.
Code Blocks
Click on the picture of any of these Scratch code blocks to see how to write similar code statements in C#.

int score = 5 + 6; // 11 int age = score + 1; // 12 int total = score + age; // 23 score += 1; // 12 score++; // 13

int score = 10 - 5; // 5 int age = score - 1; // 4 int total = score - age; // 1 score -= 1; // 4 score--; // 3

int score = 3 * 5; // 15 int age = score * 2; // 30 int total = score * age; // 450 score *= 3; // 45

int score = 10 / 3; // 3 double amount = 7.0 / 2.0; // 3.5 int total = score / score; // 1 score /= 3; // 1

int score = Random.Range(1, 11); // Could be one of [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] float time = Random.Range(0f, 1f); // Could be any value between 0 (inclusive) and 1 (inclusive) float amount = Random.value; // Could be any value between 0 (inclusive) and 1 (inclusive)

bool result = 10 > 3; // true result = 3 > 10; // false

bool result = 10 < 3; // false result = 3 < 10; // true

bool result = 10 == 10; // true result = 10 == 3; // false

bool result = true && true; // true result = true && false; // false result = false && true; // false result = false && false; // false

bool result = true || true; // true result = true || false; // true result = false || true; // true result = false || false; // false

bool test = false; // false test = !test; // true

string name = "Jon" + " the great!"; // "Jon the great!" string firstName = "Jon"; string lastName = "Parham"; string fullName = string.Concat(firstName, " ", lastName); // "Jon Parham" string[] fruits = { "banana", "grape", "strawberry" }; string allFruits = string.Join(", ", fruits); // "banana, grape, strawberry"

string name = "Jon"; string firstLetter = name.Substring(0, 1); // "J" string secondLetter = name.Substring(1, 1); // "o" string lastTwoLetters = name.Substring(1, 2); // "on"

string fruit = "apple"; int letterCount = fruit.Length; // 5

string fruit = "apple"; bool test = fruit.Contains("a"); // true test = fruit.Contains("app"); // true test = fruit.Contains("b"); // false

int mod = 10 % 3; // 1

float result = Mathf.Round(3.2f); // 3 result = Mathf.Round(3.7f); // 4

float result = Mathf.Abs(-3f); // 3

float result = Mathf.Floor(3.7f); // 3

float result = Mathf.Ceil(3.3f); // 4

float result = Mathf.Sqrt(4f); // 2

float result = Mathf.Sin(4f); // -0.7568025

float result = Mathf.Cos(4f); // -0.6536436

float result = Mathf.Tan(4f); // 1.157821

float result = Mathf.Asin(0.5f); // 0.5235988

float result = Mathf.Acos(0.5f); // 1.047198

float result = Mathf.Atan(0.5f); // 0.4636476

float result = Mathf.Log10(100f); // 2

float e = (float)System.Math.E; float result = Mathf.Pow(e, 2); // 7.389056

float result = Mathf.Pow(10, 2); // 100
Links
Here are a few links that are relevant to this material and can help you dive a little deeper if you need more help.
Summary
This should cover all of the code blocks in Scratch’s “Operators” category. If you have any questions about this reference guide feel free to ask below.
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