I want a function which takes string as an argument and add any char between string after every 3 letters.
For example:
func("11111111"){}
will return:
11,111,111
-
I've updated answer, please checkAndrii Turkovskyi– Andrii Turkovskyi2019-05-22 12:42:01 +00:00Commented May 22, 2019 at 12:42
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4 Answers
If I understand your question correctly
import 'dart:math' as math;
String convertFun(String src, String divider) {
String newStr = '';
int step = 3;
for (int i = 0; i < src.length; i += step) {
newStr += src.substring(i, math.min(i + step, src.length));
if (i + step < src.length) newStr += divider;
}
return newStr;
}
UPD: (for separating symbols from end, not from beginning)
String convertFun(String src, String divider) {
String newStr = '';
int step = 3;
for (int i = src.length - 1; i >= 0; i -= step) {
String subString ='';
if (i > 3) {
subString += divider;
}
subString += src.substring( i < step ? 0 : i - step, i);
newStr = subString + newStr;
}
return newStr;
}
answered May 21, 2019 at 14:43
Andrii Turkovskyi
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1 Comment
Anirudh Sharma
the output of 1111111 must be 1,111,111 not 111,111,1 it must start placing "," from back.
String func(String str){
RegExp exp = RegExp(r".{1,3}");
Iterable<Match> matches = exp.allMatches(str);
List<dynamic> list = [];
matches.forEach((m)=>list.add(m.group(0)));
return list.join(',');
}
Comments
Try this:
String myFunction(String str, String separator) {
String tempString = "";
for(int i = 0; i < str.length; i++) {
if(i % 3 == 0 && i > 0) {
tempString = tempString + separator;
}
tempString = tempString + str[i];
}
return tempString;
}
And use it for example, like this:
Text(myFunction("111111111", ","))
1 Comment
Anirudh Sharma
Sorry, but i forgot to mention that it must start parsing from backwards like in dollar. For example "11111"=>"111,11"not"11,111" .
The other solutions work for your stated problem, but if you are looking to add commas in numbers (as in your example), you'll want to add the comma's from the right to the left instead. ie: 12345678 you would want 12,345,678 not 123,456,78
String convertFun(String src, String divider) {
StringBuilder newStr = new StringBuilder();
int step = 3;
for (int i = src.length(); i > 0; i -= step) {
newStr.insert(0, src.substring( i < step ? 0 : i - step, i));
if (i > 3) {
newStr.insert(0, divider);
}
}
return newStr.toString();
}
