Today I asked AI to create a JavaScript to C# cheat sheet in markdown format, since I come from a strong C# background and I'm working towards improving my JavaScript skills. When I don't know how to do something the JavaScript way, I find it helpful to think in terms of C# and then translate.
This cheat sheet helps developers transition from JavaScript to C# by comparing syntax and concepts side by side.
📌 Variable Declaration
| JavaScript |
C# |
let x = 5; |
int x = 5; |
const name = "John"; |
const string name = "John"; |
var isActive = true; |
bool isActive = true; |
🔢 Data Types
| JavaScript |
C# |
| Number |
int, float, double |
| String |
string |
| Boolean |
bool |
| Object |
class |
| Array |
array or List |
| null / undefined |
null |
🔁 Loops
| JavaScript |
C# |
for (let i = 0; i < 10; i++) |
for (int i = 0; i < 10; i++) |
while (x < 10) |
while (x < 10) |
do { ... } while (x < 10) |
do { ... } while (x < 10); |
for (let item of array) |
foreach (var item in array) |
✅ Conditionals
| JavaScript |
C# |
if (x > 5) { ... } |
if (x > 5) { ... } |
else if (x < 3) |
else if (x < 3) |
else |
else |
switch (value) |
switch (value) |
📦 Functions / Methods
| JavaScript |
C# |
function greet(name) { ... } |
void Greet(string name) { ... } |
const add = (a, b) => a + b; |
int Add(int a, int b) => a + b; |
return value; |
return value; |
🧱 Classes
| JavaScript |
C# |
class Person { constructor(name) { this.name = name; } } |
class Person { public string Name; public Person(string name) { Name = name; } } |
🔧 Properties and Methods
| JavaScript |
C# |
this.name |
this.Name |
getName() |
GetName() |
🧪 Equality
| JavaScript |
C# |
== |
== |
=== |
== (type-safe) |
!= |
!= |
📚 Miscellaneous
| JavaScript |
C# |
console.log("Hi") |
Console.WriteLine("Hi"); |
typeof x |
x.GetType() |
JSON.stringify(obj) |
JsonConvert.SerializeObject(obj) (via Newtonsoft.Json) |
Feel free to expand this with more advanced topics like async/await, LINQ, events, and delegates!
