I need to compare 2 numeric strings in iOS. The first string, stored, is a fixed long number, and I want to check that the last digit of the second string entered is the same as the corresponding digit on the stored string (which isn't necessarily the last digit).
For example...
entered = 123456789
stored = 12345678902345678
In this example, I'd like to check that 9 on entered is the same as the digit in the same position on stored.
I'm thinking there's 2 possible ways of achieving this, but if there's a simpler way that'd be great...
Check the entered string length and compare the character at that position of entered and stored.
Check if the entered string is equal to the value of the corresponding length in stored.
Could someone please offer some advice in this area.
Breaking up the 'about to get stored' string in character set and comparing the 9th element (or with whatever position of element you want to compare) with the 9th element of the existing stored string.
Have a look at this: Breaking NSString 'word' in characters..
After breaking up 'about-to-get-stored' NSString in characters, take the 9th element and then get its intValue (like [lastElement intValue];) and on the other side retrieve your 'already-stored' NSString, break up in characters, take the 9th element and then get its intValue (as shown above) and now you have two int values, you can easily compare two integers..
Hope that helps a little. :)
Related
I'm creating an OCR line for our remits that our scanner will read. The scanner doesn't allow the '.' in the field - it assumes the last 2 digits are the decimal place values. I'm converting the field to to text but not sure how to remove the '.' and keep the decimal place values.
The most simple solution would be to create a Formula Field and use the Replace() function. The formula for your Formula Field would look like this:
StringVar myVariable;
myVariable := Replace({table.column}, ".", "");
myVariable;
This will search {table.column} for the first occurrence of a decimal and replace it with an empty string.
However, if your intent is to barcode the value, there may be a UFL available that could also do this for you. When creating barcodes, User Function Libraries are usually preferred because they have functions specifically designed to encode your barcode values. They aren't required though and you can always choose to manually encode barcode values manually with Formula Fields.
I have a field with the following types of string
X000233756_9981900025_201901_EUR_/
I firstly need to take take the characters to the left of the first _
Secondly I need to take the characters between the first and 2nd _
First _ is CHARINDEX('_',[Line_Item_Text],1) AS Position_1
Second _ is CHARINDEX('_',[Line_Item_Text],CHARINDEX('_',[Line_Item_Text],1)+1) AS Position_2
I was then expecting to be able to do
left([Line_Item_Text],CHARINDEX('_',[Line_Item_Text],1)-1) AS Data_1
Substring([Line_Item_Text],CHARINDEX('_',[Line_Item_Text],1)+1),CHARINDEX('_',[Line_Item_Text],CHARINDEX('_',[Line_Item_Text],1)+1) - CHARINDEX('_',[Line_Item_Text],1)+1)) AS Data_2"
Which should give me
X000233756
9981900025
But getting errors with incorrect number of functions when I start adding and subtracting from CHARINDEX Function.
Any ideas where I am going wrong?
TIA
Geoff
Actually, using the base string functions here is going to be an ugly nightmare. You might find that STRING_SPLIT along with some clever logic might be easier:
SELECT value
FROM STRING_SPLIT('X000233756_9981900025_201901_EUR_', '_')
WHERE LEN(value) > 6 AND NOT value LIKE '[A-Z]%';
This answer assumes that the third and fourth components would always be a 6 digit date and 3 letter currency code, and that the first (but not second) component would always start with some letter.
Demo
I'm trying to do a simple mail merge in Word 2010 but when I insert an excel field that's supposed to represent a zip code from Connecticut (ie. 06880) I am having 2 problems:
the leading zero gets suppressed such as 06880 becoming 6880 instead. I know that I can at least toggle field code to make it so it works as {MERGEFIELD ZipCode # 00000} and that at least works.
but here's the real problem I can't seem to figure out:
A zip+4 field such as 06470-5530 gets treated like an arithmetic expression. 6470 - 5530 = 940 so by using above formula instead it becomes 00940 which is wrong.
Perhaps is there something in my excel spreadsheet or an option in Word that I need to set to make this properly work? Please advise, thanks.
See macropod's post in this conversation
As long as the ZIP codes are reaching Word (with or without "-" signs in the 5+4 format ZIPs, his field code should sort things out. However, if you are mixing text and numeric formats in your Excel column, there is a danger that the OLE DB provider or ODBC driver - if that is what you are using to get the data - will treat the column as numeric and return all the text values as 0.
Yes, Word sometimes treats text strings as numeric expressions as you have noticed. It will do that when you try to apply a numeric format, or when you try to do a calculation in an { = } field, when you sum table cell contents in an { = } field, or when Word decides to do a numeric comparison in (say) an { IF } field - in the latter case you can get Word to treat the expression as a string by surrounding the comparands by double-quotes.
in Excel, to force the string data type when entering data that looks like a number, a date, a fraction etc. but is not numeric (zip, phone number, etc.) simply type an apostrophe before the data.
=06470 will be interpreted as a the number 6470 but ='06470 will be the string "06470"
The simplest fix I've found is to save the Excel file as CSV. Word takes it all at face value then.
I have implemented a custom keyboard associated with a text field, so when the user presses the delete button, I remove the last character from the string, and manually update the current text field text.
NSRange range = NSMakeRange(currentTextFieldString.length-1, 1);
[currentTextFieldString replaceCharactersInRange:range withString:#""];
So far so good.
Now, the problem is, that the user has the option to enter some special unicode symbols, these are not 1 byte, they can be 2 bytes too, now on pressing the delete button, I have to remove the entire symbol, but if I follow the above approach, the user has to press the delete button twice.
Here, if I do:
NSRange range = NSMakeRange(currentTextFieldString.length-2, 2);
[currentTextFieldString replaceCharactersInRange:range withString:#""];
it works fine, but then, the normal characters, which are just 1 byte, get deleted twice at a time.
How to handle such scenarios?
Thanks in advance.
EDIT:
It is strange, that if I switch to the iPhone keyboard, it handles both cases appropriately. There must be some way to do it, there is something that I am missing, but am not able to figure out what.
Here's the problem. NSStrings are encoded using UTF-16. Many common Unicode glyphs take up only one unichar (a 16 bit unsigned value). However, some glyphs take up two unichars. Even worse, some glyphs can be composed or decomposed, e.g.é might be one Unicode code point or it might be two - an acute accent followed by an e. This makes it quite difficult to do what you want viz delete one "character" because it is really hard to tell how many unichars it takes up.
Fortunately, NSString has a method that helps with this: -rangeOfComposedCharacterSequenceAtIndex:. What you need to do is get the index of the last unichar, run this method on it, and the returned NSRange will tell you where to delete from. It goes something like this (not tested):
NSUInteger lastCharIndex = [myString length] - 1; // I assume string is not empty
NSRange rangeOfLastChar = [myString rangeOfComposedCharacterSequenceAtIndex: lastCharIndex];
myNewString = [myString substringToIndex: rangeOfLastChar.location];
If you can't get this to work by default, then use an if/else block and test if the last character is part of a special character. If it is, use the substring to length-2, otherwise use the substring to length-1.
I don't know exactly what the problem is there with the special characters byte length.
What i suggest is:
Store string length to a param, before adding any new characters
If user selects backspace (remove last characters) then remove the string from last length to new length. Means for example last saved string length is 5 and new string length is 7 then remove get a new string with the index from 0 to 4, so it will crop the remaining characters.
This is the other way around to do as i don't know the exact what problem internally.
But i guess logically this solution should work.
Enjoy Coding :)
For a specialized calculator I would like to allow copy / paste for a textfield which is meant for numerical values only. So, only numerical characters should be actually pasted or the pasted string should be rejected if it contains non-numerical characters.
I was thinking about using UITextFieldDelegates textField:shouldChangeCharactersInRange:replacementString: method to check the pasted string for non-numerical characters. But NSString offers no method for checking whether it does NOT contain characters specified in a single set. So this way I would need to check occurances of characters from several sets, which is clumsy and these checks would run for every single number that would be typed in, which appears like quite some overhead to me.
Another way would be to iterate and check for every character in the replacement string whether there's a match in a numerical set.
Either way would propably work, but I feel like I'm missing something.
Do you have any advice? Is there a convenience method to achieve this?
But NSString offers no method for checking whether it does NOT contain characters specified in a single set
sure it does.
if([myString rangeOfCharacterFromSet:myCharacterSet].location ==NSNotFound)
{
//means there is no character from specified set in specified string
}