ES8 String padding
ES8 introduced the following new string methods.
- padStart
- padEnd
padding methods allow modifying strings by padding characters to string and returning the new string.
The characters add to the start or end using padStart or padEnd methods.
String padStart method
Syntax:
string padStart(destinationLength,\[,padString\])
Parameters and returns
destinationLength, length of output string after padding string characters to an input stringpadString, the characters to be added. Optional, default is space.- `returns’ output new string with length of destinationLength after padString is added.
Example
String padStart method
Padding extra characters to original string from starting index
| example | output | description |
|---|---|---|
'sentences'.padStart(9)' | sentences | if length of input is less than output, still prints original |
'sentences'.padStart(10)' | sentences | if length of input is greater than output, space padding added to start |
'sentences'.padStart(12)' | sentences | space padding added to start |
'sentences'.padStart(12,'my)' | mymsentences | padString added to start |
'sentences'.padStart(10,'my')' | msentences | padString added to start |
'sentences'.padStart(15,'my')' | mymymysentences | padString added to start |
String padEnd method
Padding string to original input string from end index
Syntax:
string padEnd(destinationLength,\[,padString\])
Parameters and returns
destinationLength, length of output string after adding string characters to the input stringpadString, the characters to be added. Optional, default is space.- `returns’ output new string with length of destinationLength after padString is added.
Example:
| example | output | description |
|---|---|---|
'hellojohn'.padEnd(9)' | hellojohn | if length of input is less than output, still prints original |
'hellojohn'.padEnd(10)' | hellojohn | if length of input is greater than output, space padding added to end |
'hellojohn'.padEnd(12)' | hellojohn | space padding added to end |
'hellojohn'.padEnd(12,'my)' | hellojohnmym | padString added to end |
'hellojohn'.padEnd(10,'my')' | hellojohnm | padString added to end |
'hellojohn'.padEnd(15,'my')' | hellojohnmymymy | padString added to end |