C # variables and Constants

VariableI,Name variable:IdentifierTo name a variable, follow the naming rules of C #: 1. The variable name can only contain letters, numbers, and underscores, it cannot contain spaces, punctuation marks, operators, and other symbols. 2. The variable name cannot be the same as the keyword name in C #. 2,SyntaxData type variable name;Data type variable name = initial value;General suggestions for variable naming:1. It is best to start the variable name with a lower-case letter. 2. The variable name should be descriptive. 3. In the variable name that contains multiple words, start with the second word, each word is capitalized.Usage principle of variables: declare first and then use!1. Naming constant definition: a constant is a constant volume declaration method:Const Data TypeConstant expression;