JavaScript string (both primitive and String object) includes a bunch of default properties and methods that can be used for for different purposes.
The global object String is a constructor for strings or a sequence o characters.
Everything in JavaScript is an object. For example when a string is created like this:
var myString = 'This is my string for testing';
the variable 'myString' becomes a string object instance. A string object instance has a vast number of properties and methods available to it.
Here follows some useful methods that can be used.
| charAt() | Returns the character at the defined position. |
| charCodeAt() | Returns the Unicode of the character at the defined position. |
| concat() | Concatenate two or more strings, and returns a new concatenated string. |
| endsWith() | Checks if a string ends with the defined string or character. |
| fromCharCode() | Converts the Unicode values to characters. |
| includes() | Checks if a string contains the defined string/character. |
| indexOf() | Returns the first position where the defined value in a string is found. |
| lastIndexOf() | Returns the last position where the defined value in a string is found. |
| localeCompare() | Compares two strings. |
| match() | Search a string with a regular expression, and returns the matches |
| repeat() | Returns a defined number of copies of an existing string. |
| replace() | Search a string for a defined value, or a regular expression. If the value is found return a new string where the specified values is replaced. |
| search() | Search a string for a defined value, or a regular expression. If it's found the position of the match is returned. |
| slice() | Extracts a part of a string and return it as a new string. |
| split() | Split up a string into an array of substrings. |
| startsWith() | Checks if a string starts with the defined character/s |
| substr() | Return the characters from a string, beginning from a defined start position and from that position return the defined number of character. |
| substring() | Return the characters from a string, between two defined posistion. |
| toLocaleLowerCase() | Converts a string to the host's locale lowercase letters. |
| toLocaleUpperCase() | Converts a string to the host's locale uppercase letters. |
| toLowerCase() | Converts a string to lowercase letters. |
| toString() | Returns the value of a String object. |
| toUpperCase() | Converts a string to uppercase letters. |
| trim() | Trim both the start and the end of a string. |
| valueOf() | Returns the primitive value of a String object. |
Here follows some useful properties that can be used.
| constructor | Returns the constructor function of a string. |
| length | Returns the length of a string |
| prototype | Use this to add properties and methods to an object |
When using special characters they can be encoded using escape notation:
\XXX |
octal Latin-1 character. |
\' |
single quote |
\" |
double quote |
\\ |
backslash |
\n |
new line |
\r |
carriage return |
\v |
vertical tab |
\t |
tab |
\b |
backspace |
\f |
form feed |
\uXXXX |
unicode codepoint |
\u{X} ... \u{XXXXXX} |
unicode codepoint |
\xXX |
Latin-1 character |
JavaScript is not like all other languages and makes no distinction between single-quoted strings and double-quoted strings. As a consquence of that strings created with either single or double quotes will behave the same.
To have the string wrapped inside a appropriate HTML tag the HTML wrapper methods can be used.
| anchor() | Is wrapping the string in a <a> tag. |
| big() | Is wrapping the string in a <big> tag. |
| blink() | Is wrapping the string in a <blink> tag. |
| bold() | Is wrapping the string in a <b> tag to make it bold in HTML. |
| fixed() | Is wrapping the string in a <tt> tag. |
| fontcolor() | Is wrapping the string in a <font color="color"> tag. |
| fontsize() | Is wrapping the string in a <font size="size"> tag. |
| italics() | Is wrapping the string in a <i> tag. |
| link() | Is wrapping the string in a <a>tag where href attribute value is set to specified string. |
| small() | Is wrapping the string in a <small>tag. |
| strike() | Is wrapping the string in a <strike> tag. |
| sub() | Is wrapping the string in a <sub>tag |
| sup() | Is wrapping the string in a <sup>tag |
Have in mind that these may not work as expected in all browsers since they are not standard methods.
The strict context prevents some actions and throws more exceptions. Strict mode changes previously accepted "bad syntax" into errors. Strict mode will for example prevent using undeclared variables. The "use strict" directive was new in ECMAScript version 5.
Date and Time are used in our everyday lives. It is important to understand how to use Date and Time in computer programming. You might have to create a website with a calendar. The application should show relevant times based on the user's current timezone.
JavaScript offers us a d....
Boolean is a primitive data type in JavaScript. Boolean can have only two values, true or false. It is useful in controlling program flow using conditional statements like if..else, switch, while, do..while.
Number methods can help you when working with number datatypes. The number methods are improved in ES6 (ECMAScript 6).
Keep reading to understand how the number methods and properties may help you.
JavaScript is one of the 3 core language technologies of the World Wide Web that all web developers must learn:
1. HTML to define the content of web pages.
2. CSS to specify the layout of web pages.
3. JavaScript to program the behavior of web pages.
JavaScript is a scripting or programming language that allows you to implement complex things on web pages. Every time a web page does more than just sit there and display static information for you to look at, displaying timely content updates, interactive maps, animated 2D/3D graphics, scrolling video jukeboxes, etc. − you can bet that JavaScript is probably involved. The benefits of using JavaScript are: 1. You can validate user input before sending the page off to the server. This saves server traffic, which means less load on your server. 2. Immediate feedback to the visitors − They don't have to wait for a page reload to see if they have forgotten to enter something. 3. Increased interactivity − You can create interfaces that react when the user hovers over them with a mouse or activates them via the keyboard. 4. Richer interfaces − You can use JavaScript to include such items as drag-and-drop components and sliders to give a Rich Interface to your site visitors.
The NDC Conferences (Norwegian Developers Conference) are one of the world`s largest independent software conferences for .NET & Agile development. The conference covers everything you need to know within software development. The conferences are held each year in many places such as Oslo, Copenhagen, London, Sydney and Minnesota.
Update Conference Prague is the biggest developer conference in the Czech Republic. The conference is offering sessions delivered by the top experts from all around the world. Their goal is to inspire the attendees and enrich their knowledge.
Learn about Web Security from Troy Hunt. He is a really engaged speaker that frequently give talks on conferences around the world. Troy is a Microsoft MVP and you can even learn from him on some great courses on Pluralsight.
W3Schools.com is a great education Web Site for learning web technologies. On W3Schools you may find well organized basic to advanced tutorials and references.
Learn about Web Technologies and new trends from Scott Hanselman. Scott Hanselman is an author of developer books and he is an engaged speaker that usually talks about the Microsoft stack. You may meet Scott on conferences around the world.
DeveloperWeek is one of the world’s largest developer conferences. Developer Week focus on new dev technologies, the conference have talks and workshops for newbies and experienced audience. You can attend on a Developer Week conference different places in Nothern America.