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.
B4X:
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)
 

Attachments

  • StringFunctions 1.0.zip
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  • StringFunctions 1.01.zip
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  • StringFunctions 1.03.zip
    7.4 KB · Views: 1,242
  • StringFunctions 1.04.zip
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  • StringFunctions 1.05.zip
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Last edited:

stanks

Active Member
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Longtime User
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.

B4X:
Dim sf As StringFunctions
sf.Initialize
Dim ans As String = sf.SplitGetWord("This is a test string.", " ", 2)
Log(ans)
i was talking about your 1st thread here. check description for SplitGetWord func
 

chrjak

Active Member
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Longtime User
nice work BUT is this lib the reason why i have a read data permission in my app?
Edit: I just saw: Yes it is.
But why needs it to write on the external storage?
How to disable this? How to explain that a string reformer uses this permission...!?
I use only split
 
Last edited:

chrjak

Active Member
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Longtime User
but you can convert it!?
(for i = 0 to string().indexes
list.add(string(i))
next)
Edit: It worked. Thanks Klaus
 
Last edited:

margret

Well-Known Member
Licensed User
Longtime User
nice work BUT is this lib the reason why i have a read data permission in my app?
Edit: I just saw: Yes it is.
But why needs it to write on the external storage?
How to disable this? How to explain that a string reformer uses this permission...!?
I use only split

The new library 1.05 has new commands(SaveData & GetData) to write and read data. This is why the permission is needed. If you use one of the previous versions, they do not require these permissions.
 

NJDude

Expert
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Longtime User
nice work BUT is this lib the reason why i have a read data permission in my app?
Edit: I just saw: Yes it is.
But why needs it to write on the external storage?
How to disable this? How to explain that a string reformer uses this permission...!?
I use only split
If you are sure you're not going to need that permission then remove it, add this line to your manifest using the manifest editor:
B4X:
RemovePermission(android.permission.WRITE_EXTERNAL_STORAGE)
 

howt

Member
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Longtime User
Hi Margret,

I have a problem with the InString-Function:
STRA = "abc"

I = fs.Instr (STRA, "abc")
I = 0? why? I would still be 1 or?

next example:
I = fs.Instr (STRA, "xyz")
I = 0, that is correct!

the other functions are great!

Walter
 

howt

Member
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Longtime User
not found = 0
Found at the first position = 0
How can I distinguish that?
In Visual basic is found the first position = 1!?
 

margret

Well-Known Member
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Longtime User
Not found = -1, anything over -1 = found. I just ran this test code:

B4X:
Log(jstr.InString("Mr. Jim Hall","Jim"))
Log(jstr.InString("Mr. Jim Hall","Bill"))
Log(jstr.InString("Mr. Jim Hall","Hall"))
Log(jstr.InString("Mr. Jim Hall","Mr"))

Log Results:

Even the arrays in B4A start at position 0 as the first element. The List items do as well.
 
Last edited:

chrjak

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Longtime User
If you are sure you're not going to need that permission then remove it, add this line to your manifest using the manifest editor:
B4X:
RemovePermission(android.permission.WRITE_EXTERNAL_STORAGE)
Wow these are great News!
Thanks!
 

sultan87

Active Member
Licensed User
Longtime User
Wow these are great News!
Thanks!
Hello Margret
I want to replace a character with another in a string
such as replacing the "K" by an "R" in the string
[Deal "N: KJ.Q63.AK743.542 AQT862.4.QJ9.T96 54.AKJT7.862.AKJ 973.9852.T5.Q873"]
I tried with sf.stuff, but it does not replace a character
there no one INSTR function as in VB
Best regards
 
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