반응형 JavaScript5 Debugging syntax errors that prevent a program from running runtime errors when code fails to execute or has unexpected behavior semantic (or logical) errors when code doesn't do what it's meant to. 2020. 2. 14. REGEX ExpressionDescription [abc] Find any character between the brackets [^abc] Find any character NOT between the brackets [0-9] Find any character between the brackets (any digit) [^0-9] Find any character NOT between the brackets (any non-digit) (x|y) Find any of the alternatives specified [ㄱ-ㅎㅏ-ㅣ가-힣] = 한글 포함 + = at least one * = zero or more var str = "Hellooo World! Hello W3Schools!"; var patt1 .. 2020. 2. 12. Regular Expressions Regular expressions are used in programming languages to match parts of strings. You create patterns to help you do that matching. QuantifierDescription n+ Matches any string that contains at least one n n* Matches any string that contains zero or more occurrences of n n? Matches any string that contains zero or one occurrences of n n{X} Matches any string that contains a sequence of X n's n{X,Y.. 2020. 2. 10. es6 var while can be called multiple times, let acts like variable from java, can be called only once if it is declared globally. var acts as global variable all the time while let functions only in the declared block. const is final from java. arrow syntax function is lamba from java. javascript allows for default value 2020. 2. 10. Basic Javascript JavaScript provides seven different data types which are undefined, null, boolean, string, symbol, number, and object. When JavaScript variables are declared, they have an initial value of undefined. If you do a mathematical operation on an undefined variable your result will be NaN which means "Not a Number". If you concatenate a string with an undefined variable, you will get a literal string .. 2020. 2. 8. 이전 1 다음 반응형
