How can I replace specified whitespaces in string?
1
I have a string:
2+3-{Some value}
How can I prevent user from adding spaces between operators and operands, but allow to add spaces between curly braces? Maybe regex?
Update
I'm working on real time validating formula. All validations including whitespace removal are done using TextWatcher. My simplified code looks like this:
private val formulaWatcher: TextWatcher = object : TextWatcher {
override fun afterTextChanged(s: Editable?) = Unit
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = Unit
override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
//Delay used here to avoid IndexOfBoundExceptions which arise because of a setSelection() method, it works with a little delay
Handler().postDelayed({
removeSpaces(s)
}, 100)
}
}
Remove spaces function:
private fun removeSpaces(s: CharSequence) {
if (s.last().isWhitespace()) {
val textWithoutSpaces = s.replace(Regex("\s"), "")
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
}
java
android string replace kotlin asked Nov 13 '18 at 8:54
SkullperSkullper
19611
add a comment |
1
I have a string:
2+3-{Some value}
How can I prevent user from adding spaces between operators and operands, but allow to add spaces between curly braces? Maybe regex?
Update
I'm working on real time validating formula. All validations including whitespace removal are done using TextWatcher. My simplified code looks like this:
private val formulaWatcher: TextWatcher = object : TextWatcher {
override fun afterTextChanged(s: Editable?) = Unit
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = Unit
override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
//Delay used here to avoid IndexOfBoundExceptions which arise because of a setSelection() method, it works with a little delay
Handler().postDelayed({
removeSpaces(s)
}, 100)
}
}
Remove spaces function:
private fun removeSpaces(s: CharSequence) {
if (s.last().isWhitespace()) {
val textWithoutSpaces = s.replace(Regex("\s"), "")
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
}
java
android string replace kotlin asked Nov 13 '18 at 8:54
SkullperSkullper
19611
1
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Maybe regex? - gooed idea usingString::replaceAll
– Scary Wombat
Nov 13 '18 at 8:59
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07
add a comment |
1
1
1
I have a string:
2+3-{Some value}
How can I prevent user from adding spaces between operators and operands, but allow to add spaces between curly braces? Maybe regex?
Update
I'm working on real time validating formula. All validations including whitespace removal are done using TextWatcher. My simplified code looks like this:
private val formulaWatcher: TextWatcher = object : TextWatcher {
override fun afterTextChanged(s: Editable?) = Unit
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = Unit
override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
//Delay used here to avoid IndexOfBoundExceptions which arise because of a setSelection() method, it works with a little delay
Handler().postDelayed({
removeSpaces(s)
}, 100)
}
}
Remove spaces function:
private fun removeSpaces(s: CharSequence) {
if (s.last().isWhitespace()) {
val textWithoutSpaces = s.replace(Regex("\s"), "")
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
}
java
android string replace kotlin asked Nov 13 '18 at 8:54
SkullperSkullper
19611
I have a string:
2+3-{Some value}
How can I prevent user from adding spaces between operators and operands, but allow to add spaces between curly braces? Maybe regex?
Update
I'm working on real time validating formula. All validations including whitespace removal are done using TextWatcher. My simplified code looks like this:
private val formulaWatcher: TextWatcher = object : TextWatcher {
override fun afterTextChanged(s: Editable?) = Unit
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = Unit
override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
//Delay used here to avoid IndexOfBoundExceptions which arise because of a setSelection() method, it works with a little delay
Handler().postDelayed({
removeSpaces(s)
}, 100)
}
}
Remove spaces function:
private fun removeSpaces(s: CharSequence) {
if (s.last().isWhitespace()) {
val textWithoutSpaces = s.replace(Regex("\s"), "")
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
}
java
android string replace kotlin java
android string replace kotlin asked Nov 13 '18 at 8:54
SkullperSkullper
19611
asked Nov 13 '18 at 8:54
SkullperSkullper
19611
edited Nov 13 '18 at 9:15
Skullper
asked Nov 13 '18 at 8:54
SkullperSkullper
19611
asked Nov 13 '18 at 8:54
SkullperSkullper
19611
asked Nov 13 '18 at 8:54
SkullperSkullper
19611
19611
1
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Maybe regex? - gooed idea usingString::replaceAll
– Scary Wombat
Nov 13 '18 at 8:59
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07
add a comment |
1
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Maybe regex? - gooed idea usingString::replaceAll
– Scary Wombat
Nov 13 '18 at 8:59
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07
1
1
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Maybe regex? - gooed idea using
String::replaceAll– Scary Wombat
Nov 13 '18 at 8:59
Maybe regex? - gooed idea using
String::replaceAll– Scary Wombat
Nov 13 '18 at 8:59
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07
add a comment |
1 Answer
1
active
oldest
votes
1
UDATE
Based on that code snippet you provided, I modified the answer.
First, use trim() function to remove spaces from the beginning and end of the input string. After trimming the string, use the following regular expression to reach the desired pattern.
private fun removeSpaces(s: CharSequence) {
// e.g. s is " 2 + 3 - { some value } "
s = s.trim()
// now s is "2 + 3 - { some value }"
// define a regex matching a pattern of characters including some spaces before and after an operator (+,-,*,/)
val re = Regex("""s*([+-*/])s*""")
// $1 denotes the group in the regex containing only an operator
val textWithoutSpaces = re.replace(s, "$1")
// textWithoutSpaces is "2+3-{ some value }"
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
The regex works in this way that finds each operator i.e. +,-,*,and / along with white spaces before and after it. By grouping the operator itself using parantheses, all patterns including extra spaces are replaced by only the operators without any extra spaces.
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:2+ {oper 1}, we will get:2+ {oper 1}
– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean2 + 3 - { any string }must be converted to2+3-{ any string }. Am I right?
– Abdollah
Nov 13 '18 at 10:43
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
|
show 1 more comment
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53277138%2fhow-can-i-replace-specified-whitespaces-in-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
UDATE
Based on that code snippet you provided, I modified the answer.
First, use trim() function to remove spaces from the beginning and end of the input string. After trimming the string, use the following regular expression to reach the desired pattern.
private fun removeSpaces(s: CharSequence) {
// e.g. s is " 2 + 3 - { some value } "
s = s.trim()
// now s is "2 + 3 - { some value }"
// define a regex matching a pattern of characters including some spaces before and after an operator (+,-,*,/)
val re = Regex("""s*([+-*/])s*""")
// $1 denotes the group in the regex containing only an operator
val textWithoutSpaces = re.replace(s, "$1")
// textWithoutSpaces is "2+3-{ some value }"
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
The regex works in this way that finds each operator i.e. +,-,*,and / along with white spaces before and after it. By grouping the operator itself using parantheses, all patterns including extra spaces are replaced by only the operators without any extra spaces.
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:2+ {oper 1}, we will get:2+ {oper 1}
– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean2 + 3 - { any string }must be converted to2+3-{ any string }. Am I right?
– Abdollah
Nov 13 '18 at 10:43
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
|
show 1 more comment
1
UDATE
Based on that code snippet you provided, I modified the answer.
First, use trim() function to remove spaces from the beginning and end of the input string. After trimming the string, use the following regular expression to reach the desired pattern.
private fun removeSpaces(s: CharSequence) {
// e.g. s is " 2 + 3 - { some value } "
s = s.trim()
// now s is "2 + 3 - { some value }"
// define a regex matching a pattern of characters including some spaces before and after an operator (+,-,*,/)
val re = Regex("""s*([+-*/])s*""")
// $1 denotes the group in the regex containing only an operator
val textWithoutSpaces = re.replace(s, "$1")
// textWithoutSpaces is "2+3-{ some value }"
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
The regex works in this way that finds each operator i.e. +,-,*,and / along with white spaces before and after it. By grouping the operator itself using parantheses, all patterns including extra spaces are replaced by only the operators without any extra spaces.
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:2+ {oper 1}, we will get:2+ {oper 1}
– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean2 + 3 - { any string }must be converted to2+3-{ any string }. Am I right?
– Abdollah
Nov 13 '18 at 10:43
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
|
show 1 more comment
1
1
1
UDATE
Based on that code snippet you provided, I modified the answer.
First, use trim() function to remove spaces from the beginning and end of the input string. After trimming the string, use the following regular expression to reach the desired pattern.
private fun removeSpaces(s: CharSequence) {
// e.g. s is " 2 + 3 - { some value } "
s = s.trim()
// now s is "2 + 3 - { some value }"
// define a regex matching a pattern of characters including some spaces before and after an operator (+,-,*,/)
val re = Regex("""s*([+-*/])s*""")
// $1 denotes the group in the regex containing only an operator
val textWithoutSpaces = re.replace(s, "$1")
// textWithoutSpaces is "2+3-{ some value }"
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
The regex works in this way that finds each operator i.e. +,-,*,and / along with white spaces before and after it. By grouping the operator itself using parantheses, all patterns including extra spaces are replaced by only the operators without any extra spaces.
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
UDATE
Based on that code snippet you provided, I modified the answer.
First, use trim() function to remove spaces from the beginning and end of the input string. After trimming the string, use the following regular expression to reach the desired pattern.
private fun removeSpaces(s: CharSequence) {
// e.g. s is " 2 + 3 - { some value } "
s = s.trim()
// now s is "2 + 3 - { some value }"
// define a regex matching a pattern of characters including some spaces before and after an operator (+,-,*,/)
val re = Regex("""s*([+-*/])s*""")
// $1 denotes the group in the regex containing only an operator
val textWithoutSpaces = re.replace(s, "$1")
// textWithoutSpaces is "2+3-{ some value }"
getText().clear()
append(textWithoutSpaces)
setSelection(textWithoutSpaces.length)
}
The regex works in this way that finds each operator i.e. +,-,*,and / along with white spaces before and after it. By grouping the operator itself using parantheses, all patterns including extra spaces are replaced by only the operators without any extra spaces.
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
edited Nov 13 '18 at 18:13
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
answered Nov 13 '18 at 9:07
AbdollahAbdollah
10011
10011
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:2+ {oper 1}, we will get:2+ {oper 1}
– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean2 + 3 - { any string }must be converted to2+3-{ any string }. Am I right?
– Abdollah
Nov 13 '18 at 10:43
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
|
show 1 more comment
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:2+ {oper 1}, we will get:2+ {oper 1}
– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean2 + 3 - { any string }must be converted to2+3-{ any string }. Am I right?
– Abdollah
Nov 13 '18 at 10:43
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
1
1
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:
2+ {oper 1}, we will get: 2+ {oper 1}– Skullper
Nov 13 '18 at 9:11
thanks, but this not working. Because it's deleting spaces only from start and end. If we paste string like this:
2+ {oper 1}, we will get: 2+ {oper 1}– Skullper
Nov 13 '18 at 9:11
From your update and comments, I think you mean
2 + 3 - { any string } must be converted to 2+3-{ any string }. Am I right?– Abdollah
Nov 13 '18 at 10:43
From your update and comments, I think you mean
2 + 3 - { any string } must be converted to 2+3-{ any string }. Am I right?– Abdollah
Nov 13 '18 at 10:43
1
1
yes, you're right
– Skullper
Nov 13 '18 at 11:58
yes, you're right
– Skullper
Nov 13 '18 at 11:58
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Skullper I added a regex to the solution and tested it. It works fine.
– Abdollah
Nov 13 '18 at 18:07
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
@Abdolah Wow, thank you it really helps. I have tried regex with look-ahead, but your solution is more sophisticated)
– Skullper
Nov 13 '18 at 18:22
|
show 1 more comment
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53277138%2fhow-can-i-replace-specified-whitespaces-in-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
1
Please read "How to create a Minimal, Complete, and Verifiable example". Then use the edit link to improve your question (do not add more information via comments). Otherwise we are not able to answer your question and help you. Show us a complete example, and the code you have, and tell us where it deviates from your expectations.
– GhostCat
Nov 13 '18 at 8:55
Maybe regex? - gooed idea using
String::replaceAll– Scary Wombat
Nov 13 '18 at 8:59
@ScaryWombat replaceAll will replace all whitespaces in string. I need to save spaces between curly braces
– Skullper
Nov 13 '18 at 9:07