String Methods

Question 1

Property that returns the length of a string

Answer 1

String.length

Question 2

Returns the index of the first occurrence of a specified string in a string

Answer 2

indexOf()

Question 3

Returns the index of the last occurrence of a specified text in a string by searching backwards

Answer 3

lastIndexOf()

Question 4

indexOf() and lastIndexOf() return what if the text is not found?

Answer 4

-1

Question 5

How to add a starting position for indexOf()/lastIndexOf()

Answer 5

indexOf(string, 15)

Question 6

Searches for a string with a specified value and returns the position to the match

Answer 6

search()

Question 7

What is the difference between search() and indexOf()?

Answer 7

search() cannot take a second start position argument.

indexOf() cannot take powerful search values/regular expressions

Question 8

Extracts the part of a string and returns the extracted part in a new string with the second parameter specifying the end index.

Answer 8

slice(start, end*)

*end can be ommited to slice out the rest of the string. a negative start can be used to count from the end.

Question 9

Extract the part of a string and returns the extracted part in a new string but cannot take a negative index.

Answer 9

substring(start, end)

Question 10

Extract the part of a string and returns the extracted part in a new strung with the second parameter specifying length

Answer 10

substr(start, length)

a negative start can be used to count from the end.

Question 11

Replaces the specified value with another value in a string

Answer 11

replace()
*To replace case insensitive, use a regular expression with an /i flag (insensitive)
*
To replace all matches, use a regular expression with a /g flag (global match):

Question 12

Convert a string to uppercase

Answer 12

toUpperCase()

Question 13

Convert a string to lowercase

Answer 13

toLowerCase()

Question 14

Joins two or more strings. works like a plus operator

Answer 14

concat()

Question 15

Remove white space from both sides of a string

Answer 15

trim()

*not supported by internet Explorer 8. Use replace() with a regular expression instead.

Question 16

Returns the character at a specified index in a string

Answer 16

CharAt()

Question 17

Returns the unicode of the character at a specified index in a string (in UTF-16 code, an int between 0 and 65535)

Answer 17

CharCodeAt()

Question 18

How does property access work in a string?

Answer 18

• It makes strings look like arrays (but they are not)
• If no character is found, [ ] returns undefined
• It is read only. str[0] = “A” gives no error (but does not work!)

Question 19

Convert a string to an array

Answer 19

split(seperator*)

*takes in a string as separator. if omitted, returns an array with the whole string in index[0]