length Returns the length of the string 2.0 3.0 1.0
indexOf() Returns the index of the first time the specified
character occurs, or -1 if it never occurs, so with
that index you can determine if the string contains
the specified character. 2.0 3.0
lastIndexOf() Same as indexOf, only it starts from the right and
moves left. 2.0 4.0
match() Behaves similar to indexOf and lastIndexOf, but
the match method returns the specified characters,
or "null", instead of a numeric value. 4.0 4.0
substr() Returns the characters you specified: (14,7)
returns 7 characters, from the 14th character. 4.0 4.0
substring() Returns the characters you specified: (14,7)
returns all characters between the 7th and the 14th. 2.0 3.0 1.0
toLowerCase() Returns the string in lower case 2.0 3.0 1.0
toUpperCase() Returns the string in upper case 2.0 3.0 1.0
Examples
1.The length() Method
Use the length property to find out how many character there is
in the string.
Coding
<html>
<body>
<script language="JavaScript">
var str="how many characters"
document.write(str.length)
</script>
</body>
</html>
Output
19
2.The indexOf() Method
Test if a string contains a specified character. Returns an
integer if it does and -1 if it do not. Use this method in a
form validation.
Coding
<html>
<body>
<script language="JavaScript">
var str="W3Schools"
var character=str.indexOf("School")
document.write(character + "<br>")
if (character>=0)
{
document.write("The string contains the specified character")
}
</script>
</body>
</html>
Output
2
The string contains the specified character
3.The match() Method
Works similar to the indexOf method, only this method returns
the characters you specified, "null" if the string do not
contain the specified characters.
Coding
<html>
<body>
<script language="JavaScript">
var str = "W3Schools are great"
document.write(str.match("great"))
</script>
</body>
</html>
Output
great
4.The substr() Method
The substr method returns specified parts of the string. If you
specify (14,7) the return will be the 14th character and the
next 7. Note that the first character is 0, the second is 1 etc.
Coding
<html>
<body>
<script language="JavaScript">
var str="W3Schools are great"
document.write(str.substr(3,6))
</script>
</body>
</html>
Output
chools
5. The toLowerCase() toUpperCase() Method
How to return a string in lower or upper case.
Coding
<html>
<body>
<script language="JavaScript">
var str=("Hello JavaScripters!")
document.write(str.toLowerCase())
document.write("<br>")
document.write(str.toUpperCase())
</script>
</body>
</html>
Output
hello javascripters!
HELLO JAVASCRIPTERS