B4A Library String Functions

Updated: 3/14/2014 - Version 1.05, This new version has 14 new functions/commands. Please report any issues. The new functions/commands are underlined and listed below in the updated docs.

Updated: 9/19/2013 - Version 1.04, Corrected an error in the Mid() function when retrieving the last character.

Updated: 8/28/2013 - Version 1.03, Added code to stop OutOfBounds error on the Mid Function. This would happen when an invalid index was passed to the function. Also corrected a bug that was in the DayOfMonth Function in versions prior to 1.02.

Updated: 4/5/2013 Added new date functions and a simple Encrypt and Decrypt Function. NOTE: A few older Functions were renamed.

StringFunctions use function names that are closer to the VB commands and may help beginners when they start programming in B4A. I wrote them for that reason when I started. These functions use to be in a code module but have now been converted to a Library. This has the new inline syntax and help as you start to type the command.

Requires B4A 2.5 or Higher
Copy the StringFunctions.jar and StringFunctions.xml to the Extra Libraries folder.

Be sure to DIM the Lib object like Below. You can use any variable name in place of sf in the Example below.

Sub Globals
   Dim sf As StringFunctions
   sf.Initialize
End Sub

StringFunctions Version 1.05

• AsciiCodes
  Displays a MessageBox with all Characters and their ASCII codes.
• AddSpaces (HowMany As Int) As String
  Returns a string of spaces. The number returned is set by HowMany.
• At (YourString As String, SearchFor As String))
  Returns the position of the SearchFor within YourString.
• CurrentWeek (MyDate As String) As Int
  Returns the number of the current week, 1-52 from the date passed to MyDate.
• DayOfMonth (MyDate As ) As Int
  Returns the day of the month like 1-31, from the date passed to MyDate.
• Decrypt (YourText As String) As String
  Converts an encrypted string of text to readable format, no key is needed.
• Empty (StringText As String) As Boolean
  Test to see if the string is empty and returns True if it is, otherwise returns False.
• Encrypt (YourText As String) As String
  Converts a string of text to simple encryption, no Key is needed.
• EraseData
  This will erase all data saved with the SaveData function stored in the
  temporary vault.
• FileExist (PathAndFileName As String) As Boolean
  Returns True if the filename passed does exist, otherwise returns False.
  Be sure to include the path like:
  If FileExist("/mnt/sdcard/mydata.dat") Then MsgBox("Yes", "The Answer")
• GetData (Key As Object) As Object
  Gets data from the temporary vault.
  EditText1.Text = SF.GetData("EnteredName")
  The Key is case sensitive.
• InString (YourString As String, SearchFor As String))
  Returns the position of the SearchFor within YourString.
• IsEmpty (StringText As String) As Boolean
  Test to see if the string is empty and returns True if it is, otherwise returns False.
• Left (StringText As String, Length As Long) As String
  Returns the Left portion of a string with the number of characters passed
  in Length.
• Len (StringText As String) As Long
  Returns the length of the string.
• ListToString (YourList As List, Sorted As Boolean, Ascending As Boolean) As String
  Converts a List object to a String.
• ListToStringArray (YourList As List, Sorted As Boolean, Ascending As Boolean) As String()
  Converts a List object to a String Array.
• Lower (StringText As String) As String
  Returns the string converted to Lowercase characters.
• Ltrim (StringText As String) As String
  Returns a new string with the leading spaces removed.
• MB (Message As String)
  Same as MsgBox but only needs one parameter.
• Mid (StringText As String, Start As Int, Length As Int) As String
  Returns the a new String for how ever many characters passed in Length from
  a starting position passed in Start.
  Example:
  Mid("This is a long line of text", 5, 2)
  In this example the function will Return: "is"
• MidExtract (StringText As String, Start As String, EndAt As String) As String
  Used to extract text from a string between to other blocks of text.
  Ans = MidExtract("Dr. Jim Joe Brown", "Jim", "Brown") 'Returns: Joe
  Ans = MidExtract("Dr. Jim [Joe] Brown", "[", "]") 'Returns: Joe
• MidS (StringText As String, StartAt As Int) As String
  Works like the Mid$ function in Visual Basic.
• Month (MyDate As String) As Int
  Returns the number of the current month 1-12 as Int type, from the date passed to MyDate.
• MonthName (MyDate As String) As String
  Returns the Name the current month as a String like January, etc., from the date passed to MyDate.
• NewDate (DatePassed As String, HowManyDays As Int) As String
  Returns a new date adding or subtracting HowManyDays. HowManyDays can be positive or
  negative numbers.
• NumOfDaysBetween (CurrentDate As String, OtherDate As String) As Int
  Returns the numbers of days passed between the two dates passed.
• Pad (Text As String, PadWith As String, Length As Int, Post As Boolean) As String
  Used to pad a string with a selected character. If Post = True the padding will follow
  any text in the string, if Post = False, the padding will be before the text. Length is
  the total length for the padded string. PadWith is the selected character to use for the
  padding.
  SF.Pad("Jimmy Joe", "*", 20, True) 'Returns "Jimmy Joe***********"
• Proper (StringText As String) As String
  Returns the string in proper format.
  Example:
  MyText = "jim joe brown"
  MyText = SF.Proper(Mytext)
  This function will return: "Jim Joe Brown"
• Replicate (mChar As String, Times As Int) As String
  Repeats any character passed, a selected number of Times.
• Right (StringText As String, Length As Long) As String
  Returns the Right portion of a string with the number of characters passed
  in Length.
• RndChrGen (StringLength As Int, CharacterType As Int) As String
  Returns a string of ramdom characters with a length specified by StringLength. CharacterType tells
  the function what type of characters to return.
  CharacterType = 0 for Upper and Lower case
  CharacterType = 1 for Upper case only
  CharacterType = 2 for Lower case only
• Rtrim (StringText As String) As String
  Returns a new string with the trailing spaces removed.
• SaveData (Key As Object, Data As Object)
  Save data passed in a temporary file.
  SF.SaveData("ScreenTitle", MyVar)
  or
  SF.SaveData("EnteredName", EditText1.Text)
• ScrInfo ( As Pect) As Int
  Returns information about the devices screen. You can pass these parameters:
  Pass "W" for Width
  Pass "H" for Height
  Pass "S" for Scale
  Pass "D" for DPI
  Call like: SF.ScrInfo("W")
• SearchDate (Date1 As String, Date2 As String, DateRange As Int) As Boolean
  Returns True if the Date1 and the Date2 are within x Days(DateRange) of each other.
  Pass the dates as Strings.
  Example:
  SearchDate("03/01/2013", "02/15/2013", 30)
• Split (CurrentString As String, Split_At_Delimiter As String) As List
  Returns a LIST of items from the string split at the Delimiter.
  EXAMPLE:
  Dim ANS As List
  ANS = SF.Split("This is a test string.", " ")
• SplitGetWord (CurrentString As String, Split_At_Delimiter As String, GetElement As Int) As String
  Returns just the one element selected with GetElement from the string.
  EXAMPLE:
  ANS = SF.SplitGetWord("This is a test string.", " ", 2)
  In this example the function will Return: "is"
• StrArraySort (StringArray() As String, Ascending As Boolean) As String()
  Used to sort a String Array. Sort will be in Ascending order if Ascending = True.
• StringArrayToList (StringArray() As String, Sorted As Boolean, Ascending As Boolean) As List
  Converts a String Array to a List object.
• StringToList (StringText As String, Sorted As Boolean, Ascending As Boolean) As List
  Convert a String to a List object. This will split the string between words.
• Stuff (CurrentText As String, InsertInString As String, RemoveFromString As String) As String
  Used to replace text in a string with new text.
  Example:
  MyText = "I will tell you that joe is a good friend!"
  MyText = SF.Stuff(MyText, "Joe Brown", "joe")
  This function will return: "I will tell you that Joe Brown is a good friend!"
• Today () As String
  Returns the devices date.
• Trim (Text As String) As String
  Returns a new string with leading and trailing spaces removed.
• Upper (StringText As String) As String
  Returns the string converted to Uppercase characters.
• Val (StringText As String) As Double
  Returns the numerical value of a string. If the string contains now value it returns 0.
• ValidDate (ChkDate As ) As Boolean
  Returns True if the date passed is a Valid date.
• WeekDay (MyDate As String) As String
  Returns the number of the day of the week 1-7 as a String, from the date passed to MyDate.
• WeekName (MyDate As String) As String
  Returns the name of the day of the week like Sunday, Monday, etc., from the date passed to MyDate.
• Year (MyDate As String) As String
  Returns the year of the date passed in MyDate.
  Example:
  SF.Year("01/01/2013") returns "2013"
• getSDCardPath () As String
  Returns external/physical SD Card directory. This function may not return the correct store
  on an Android OS above 4.1. This is due to changes made to the OS system in the newer versions.
  Returns "", if the store can not be read.
• iif (Value1 As String, Value2 As String, Value3 As String) As String
  This is a single line if conditional test. If Value1 is true, Value2 is returned, otherwise
  Value3 will be returned. Works with strings and booleans.
  Example:
  MsgBox(iif("Bob"="Jim", "They are the same", "They are not the same"), "The Answer")
  or
  MyBoolean = iif(FirstTime = True, StartMyService = True, StartMyService = False)

 

[margret]

Dear all,
I have below error while compling. Please help. Many thanks

Jonh

sf.Initialize
javac 1.7.0_07
src\b4a\example\main.java:311: error: cannot access ImplB4AClass
mostCurrent._sf._vvv1(processBA);
^
class file for anywheresoftware.b4a.B4AClass$ImplB4AClass not found
1 error

Please post a sample project and I will be glad to check it. You don't show it, but did you also Dim the object? Also, try to compile in Release mode only.

 

[margret]

Margret, thanks sop much for all your hard work. I do think I found a little bug in your MID function. While parsing bytes out of a hex string. I had to add an extra character for the last "byte" to be pulled without causing an OutOfBounds exception.

It was a bug. I have updated and corrected this. It is attached to post #1 of this thread as Version 1.04. Please let me know if you find any other issues.

 

[ttsolution]

My problam was solved. Many thanks Margret

Jonh

 

[ralphie911]

It was a bug. I have updated and corrected this. It is attached to post #1 of this thread as Version 1.04. Please let me know if you find any other issues.

Thanks for your super quick response, You're Unbelievable

 

[imgsimonebiliato]

Hello, my program goes on Error when I declare the
Dim sf As StringFunctions
Why? I declared it on Globals

 

[NJDude]

What's the error?

 

[imgsimonebiliato]

The application block

 

[NJDude]

Dude, POST the error message without it we can't help you.

 

[imgsimonebiliato]

I solved... Sorry

 

[NJDude]

This addition might be useful (to fulfill a request HERE)

Sub FixAndPad(Variable As String, Length As Int, Character As String, Position As String) As String
 
    Dim Padding As String
 
    Length = Abs(Length)
 
    If Character.Length = 0 Then Character = " " 
    If Position.Length = 0 Then Position = "R"
 
    For I = 0 To Length
 
        Padding = Padding & Character
 
    Next
 
    If Position = "R" Then
 
       Variable = Variable & Padding 
       Variable = Variable.SubString2(0, Length)
 
    Else
 
       Variable = Padding & Variable 
       Variable = Variable.SubString2(Variable.Length - Length, Variable.Length)
 
    End If
 
    Return Variable
 
End Sub

This function will fix the size of the string and pad it with any character, e.g.

Msgbox(FixAndPad("Hello", 10, "*", "L") '<- This will display *****Hello
 
Msgbox(FixAndPad("Hello", 10, "*", "R") '<- This will display Hello*****

 

[tucano2000]

Thanks Margret,

I am using split function in my project.

What the lowest api level to this library ?

 

[alanyu]

I have a string, "aaa .... [ bbb ... ] ccc ..."
How to get"bbb..."
Can you add the following features?

Mid (StringText As String, Start As String, Length As String) As String

Example:

Mid("aaa .... [bbb ... ] ccc ...", "[", "]")
In this example the function will Return: "bbb ... "

 

[margret]

This code should work. I will have to add this to the library when I get time.

'Call Like Below:
'MyAnswer = GetStrBlock("aaa .... [ bbb ... ] ccc ...", "[", "]")
Sub GetStrBlocK(Text As String, StartChar As String, EndChar As String) As String
     Dim s As StringFunctions : s.Initialize
     Dim a = Text As String
     Dim ans As String
     ans = s.Left(a, s.At(a, EndChar))
     ans = s.Trim(s.Right(ans, s.At(ans, StartChar)))
     Return ans
End Sub

 

[stanks]

little fix (page 1)....SplitGetWord example will return "is" and note test

 

[margret]

Which version are you using? I would like to check this.

 

[margret]

I just ran this test code in the latest version and it returns the word "is", which is the second word and the correct one. So this is working as it should.

Dim sf As StringFunctions
sf.Initialize
Dim ans As String = sf.SplitGetWord("This is a test string.", " ", 2)
Log(ans)

 

[margret]

New Version 1.05 online. See first post for new functions/commands and to download 1.05, Click Here

 

[Beja]

Thank you Margret for the useful library.

Where can I find the text of the functions? I just downloaded the 2 lib files.

 

[Beja]

Sorry.. just found it listed on the first post.. how am I thinking!

 

[NJDude]

You have a few typos on the tooltips:

1- You need to correct the tooltip for MID, the sample you have is missing quotes, that might confuse the newbies.

2- You have typed "negitive" instead of Negative in NewDate

3- You have "lendth" instead of Length in PAD

4- On StrArraySort you have misspelled Ascending, you have entered "Accending"

5- On TRIM, you have "will" instead of With

Nice lib, keep up the good work.