Strings¶
In this chapter we are going to learn about strings creation and manipulation.
String Literals¶
Syntax:
cStr = "This is a string"
cStr2 = 'Another string'
cStr3 = :JustAnotherString
cStr4 = `Yet "another" 'string' ! `
Get String Length¶
We can get the string length (letters count inside a string) using the len() function
Syntax:
len(string) ---> string length
Example:
cStr = "How are you?"
see cStr + nl
see "String size : " + len(cStr) + nl
Convert Letters Case¶
Syntax:
lower(string) ---> convert string letters to lower case
upper(string) ---> convert string letters to UPPER case
Example:
cStr = "Welcome To The Ring Programming Language"
see cStr + nl + upper(cStr) + nl + lower(cStr)
Access String Letters¶
We can access a letter inside a string by the letter index
Syntax:
string[index] ---> get string letter
string[index] = letter # set string letter
Example:
# print user name letter by letter (each letter in new line)
See "Hello, Enter your name : " give cName
for x = 1 to len(cName)
see nl + cName[x]
next
We can use for in to get string letters.
Example:
# print user name letter by letter (each letter in new line)
See "Hello, Enter your name : " give cName
for x in cName
see nl + x
next
We can modify the string letters
Example:
# convert the first letter to UPPER case
See "Enter your name : " give cName
cName[1] = upper(cName[1])
see "Hello " + cName
Left() Function¶
We can get a specified number of characters from a string using the Left() function.
The starting position is 1.
Syntax:
Left(string,count)
Example:
see left("Hello World!",5) # print Hello
Right() Function¶
We can get a specified number of characters from a string using the Right() function.
The starting position is the last character on the right.
Syntax:
Right(string,count)
Example:
see Right("Hello World!",6) # print World!
Trim() Function¶
We can remove all leading and trailing spaces from a string using the Trim() function.
Syntax:
trim(string)
Example:
cMsg = " Welcome "
see trim(cMsg) # print Welcome
Copy() Function¶
We can duplicate a string more than one time using the copy() function.
Syntax:
copy(string,nCount) ---> string replicated nCount times
Example
see copy("***hello***",3) # print ***hello******hello******hello***
Lines() Function¶
We can count the number of lines inside a string using the Lines() function.
Syntax:
lines(string) ---> Number of lines inside the string
Example:
cStr = "Hello
How are you?
are you fine?"
see lines(cStr) # print 3
Substr() Function¶
We can work on sub strings inside a string using the substr() function. Using Substr() we can
- Find substring
- Get substring from position to end
- Get Number of characters from position
- Transform Substring To Another Substring
Find substring¶
Syntax:
substr(string,substring) ---> the starting position of substring in string
Example:
cStr = "Welcome to the Ring programming language"
see substr(cStr,"Ring") # print 16
Get substring from position to end¶
Syntax:
substr(string,position) ---> Get substring starting from position to end
Example:
cStr = "Welcome to the Ring programming language"
nPos = substr(cStr,"Ring") # nPos = 16
see substr(cStr,nPos) # print Ring programming language
Get Number of Characters From Position¶
Syntax:
substr(string,position,count) ---> Get characters starting from position
Example:
cStr = "Welcome to the Ring programming language"
nPos = substr(cStr,"Ring") # nPos = 16
see substr(cStr,nPos,4) # print Ring
Transform Substring To Another Substring¶
Syntax:
substr(string,substring,newsubstring) ---> Transformed string (Match case)
substr(string,substring,newsubstring,1) ---> Transformed string (Ignore case)
Example:
cStr = "Welcome to the New programming language"
see substr(cStr,"New","Ring") + nl # print Welcome to the Ring programming language
see substr(cStr,"new","Ring",1)+ nl # print Welcome to the Ring programming language
strcmp() Function¶
We can compare between two strings using the strcmp() function.
Syntax:
strcmp(cString1,cString2) ---> value = 0 if cString1 = cString2
value < 0 if cString1 < cString2
value > 0 if cString1 > cString2
Example:
see strcmp("hello","hello") + nl +
strcmp("abc","bcd") + nl +
strcmp("bcd","abc") + nl
Output:
0
-1
1
str2list() and list2str() Functions¶
We can convert string lines to list items using the str2list() function. Also we can convert the list to a string using list2str() function.
Syntax:
str2list(string) ---> list contains the string lines
list2str(list) ---> string contains the list items
Example:
/* output:
** Items : 4
** Item : Hello
** Item : How are you ?
** Item : are you fine ?
** Item : ok
** list2Str result = Hello
** How are you ?
** are you fine ?
** ok
** Done
*/
mystr = "Hello
How are you ?
are you fine ?
ok"
mylist = str2list(mystr)
see "Items : " + len(mylist) + nl
for x in mylist
see "Item : " + x + nl
next
newstr = list2str(mylist)
see "list2Str result = " + newstr
if mystr = newstr
see nl + "Done"
else
see nl + "Error!"
ok