What is the difference between using single quotes and double quotation marks in C #?

It is different from PHP where they are almost interchangeable.

Single quotes or apostrophes are only used to delimit a single character (type char - UTF-16).

Double quotes serve to delimit a string , that is, an immutable collection of chars with a specific format.

The error indicates that it has more than one character. As it is a text and not just a character, just put double quotation marks.

strings can be defined with some prefixes to facilitate certain operations:

• What does the "$" symbol mean before a string?
• What does the "@" sign in C # mean?

Unlike PHP, in C #, they represent two different types.

Simple quotes serve to delimit a single character (type char ).

Double quotes serve to delimit a string (which is an immutable collection of chars ).

The error, in your case, occurs because there is more than one character between single quotes. What you intend to use there is a string , so just change the single quotes to double.

Example:

char meuChar = 'A';
char[] meuCharArray = { 'O', 'L', 'Á' };
string minhaString = "OLÁ";

Some other languages also work that way.

The single quotes represent a char, so they should be used ONLY to assign characters. Ex:

char sexo = 'M';

Double quotes represent a string (a collection of char). Ex:

string sexo = "masculino";

Note that a String (string, or array of char) may contain only one character, but a NEVER character may contain more than one character. Ex:

string sexo = "M"; // Correto, uma cadeia de caracteres pode conter apenas um caractere.
char sex = 'sexo'; // Erro de compilação, um char não pode conter mais que um caractere.