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Len (programming)

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Many common programming languages operate on strings using string functions. One of the major string functions Len, returns the length of a specific string.

This function is called Len, which stands for length, in the BASIC programming language and its derivatives such as Visual Basic. It is called strlen in the C programming language and its derivatives such as PHP. In some other programming languages, the entire word "length" is written out as the name of the function. For other languages see string functions.

Usage in Other Languages

To see a list of usages in other languages see the length section in

Usage in Visual Basic

In Visual Basic, the prototype of the Len function is as follows:

 Function Len (ByVal Str As String)

An example below shows an example of the use of Len function.

Sub Main()
    Dim Str As String
    Dim Int As Integer
    Str = InputBox("Enter a string")
    Int = Len(Str)
    MsgBox(CStr(Int))
End Sub

This function reads a string from an input box and outputs its length.

For example, the input "Hello!" will output 6.

Usage in Python

In Python and can be used to indicate the length of a string, it prints the number of every character in the string specified within the parentheses:

>>> something = 'Wikipedia'
>>> len(something)
9

where the word "Wikipedia" clearly has 9 letters. Consider also the example of "I am John"

>>> len('I am John')
9

because "I am John" clearly has 9 characters (keep in mind that spaces are counted as well).

The command len() can also be used with lists, here the list p includes 3 entries:

>>> p = ['Wikipedia', 'Wiktionary', 'Wikibooks']
>>> len(p)
3