Basic JavaScript Notes

Compound assignments += -= *= /=

/// @notice augmented addition
const myVariable += 2;
/// @notice augmented subtraction
const myVariable -= 2;
/// @notice augmented multiplication
const myVariable *= 2;
/// @notice augmented division
const myVariable /= 2;

Escaping literal quotes \ before "

const myVariable = 'backslash before, let\'s use "quotation marks" inside a string.';

Single quotation marks ' vs. double "

/** 
@notice When using both single and double quotation marks inside a string one must use the proper escape sequence, because if you have that same quotation mark somewhere in the middle, the string will stop early and throw an error.   
*/
const myVariable = 'backslash before, let\'s use "quotation marks" inside a string.';
/// @notice The use of single quotation marks allows the proper use of double quotation marks inside the string.
const myVariable = '<a href="http://www.example.com" target="_blank">Link</a>';

Escape sequences

Command	Description
\'	Single Quotation Mark
\"	Double Quotation Mark
\\	Backslash
\n	New Line
\r	Carriage Return
\t	Tab
\b	Word Boundry
\f	Form Feed

const myString = "FirstLine\n\t\\SecondLine\nThirdLine";
console.log(myString); 
/** @notice output:
FirstLine
	\SecondLine
ThirdLine
*/

Concatenating strings.

/** 
@notice Use the += operator to concatenate a string onto the end of an existing string variable. This can be very helpful to break a long string over several lines. 
*/
/// @notice Concatenation does not add spaces between concatenated strings, so you'll need to add them yourself.
let myVariable = "This is the first sentence. "; 
myVariable += "This is the second sentence.";

Constructing strings with variables.

/** @notice By using the concatenation operator + you can insert one or more variables into a string you're building.
*/
const myName = "WrappedUsername";
let myVariable = "Hellos my name is " + myName + ", how are you?";

Appending variables to strings.

/// @notice Appending variables to a string using the plus equals += operator.
const someAdjective = "interesting!";
let myVariable = "Learning to code is ";
myVariable += someAdjective;

Find the length of a string.

/// @notice Find the length of a String value by writing .length after the string variable or string literal.
let myNameLength = 0;
const myName = "WrappedUsername";
console.log(myName.length);
myNameLength = myName.length;

In Conclusion

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