如何将输入限制为只接受数字？

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最佳答案

Easy way, use type="number" if it works for your use case:

<input type="number" ng-model="myText" name="inputName">

Another easy way: ng-pattern can also be used to define a regex that will limit what is allowed in the field. See also the "cookbook" page about forms.

Hackish? way, $watch the ng-model in your controller:

<input type="text"  ng-model="myText" name="inputName">

Controller:

$scope.$watch('myText', function() {
// put numbersOnly() logic here, e.g.:
if ($scope.myText  ... regex to look for ... ) {
// strip out the non-numbers
}
})

Best way, use a $parser in a directive. I'm not going to repeat the already good answer provided by @pkozlowski.opensource, so here's the link: https://stackoverflow.com/a/14425022/215945

All of the above solutions involve using ng-model, which make finding this unnecessary.

Using ng-change will cause problems. See AngularJS - reset of $scope.value doesn't change value in template (random behavior)

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Using ng-pattern on the text field:

<input type="text"  ng-model="myText" name="inputName" ng-pattern="onlyNumbers">

Then include this on your controller

$scope.onlyNumbers = /^\d+$/;

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Here's my implementation of the $parser solution that @Mark Rajcok recommends as the best method. It's essentially @pkozlowski.opensource's excellent $parser for text answer but rewritten to only allow numerics. All credit goes to him, this is just to save you the 5 minutes of reading that answer and then rewriting your own:

app.directive('numericOnly', function(){
return {
require: 'ngModel',
link: function(scope, element, attrs, modelCtrl) {


modelCtrl.$parsers.push(function (inputValue) {
var transformedInput = inputValue ? inputValue.replace(/[^\d.-]/g,'') : null;


if (transformedInput!=inputValue) {
modelCtrl.$setViewValue(transformedInput);
modelCtrl.$render();
}


return transformedInput;
});
}
};
});

And you'd use it like this:

<input type="text" name="number" ng-model="num_things" numeric-only>

Interestingly, spaces never reach the parser unless surrounded by an alphanumeric, so you'd have to .trim() as needed. Also, this parser does NOT work on <input type="number">. For some reason, non-numerics never make it to the parser where they'd be removed, but they do make it into the input control itself.

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I know this is old, but I've created a directive for this purpose in case anyone is looking for an easy solution. Very simple to use.

You can check it out here.

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There are a few ways to do this.

You could use type="number":

<input type="number" />

Alternatively - I created a reuseable directive for this that uses a regular expression.

Html

<div ng-app="myawesomeapp">
test: <input restrict-input="^[0-9-]*$" maxlength="20" type="text" class="test" />
</div>

Javascript

;(function(){
var app = angular.module('myawesomeapp',[])
.directive('restrictInput', [function(){


return {
restrict: 'A',
link: function (scope, element, attrs) {
var ele = element[0];
var regex = RegExp(attrs.restrictInput);
var value = ele.value;


ele.addEventListener('keyup',function(e){
if (regex.test(ele.value)){
value = ele.value;
}else{
ele.value = value;
}
});
}
};
}]);
}());

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Here is a Plunker handling any situation above proposition do not handle.
By using $formatters and $parsers pipeline and avoiding type="number"

And here is the explanation of problems/solutions (also available in the Plunker) :

/*
*
* Limit input text for floating numbers.
* It does not display characters and can limit the Float value to X numbers of integers and X numbers of decimals.
* min and max attributes can be added. They can be Integers as well as Floating values.
*
* value needed    |    directive
* ------------------------------------
* 55              |    max-integer="2"
* 55.55           |    max-integer="4" decimal="2" (decimals are substracted from total length. Same logic as database NUMBER type)
*
*
* Input type="number" (HTML5)
*
* Browser compatibility for input type="number" :
* Chrome : - if first letter is a String : allows everything
*          - if first letter is a Integer : allows [0-9] and "." and "e" (exponential)
* Firefox : allows everything
* Internet Explorer : allows everything
*
* Why you should not use input type="number" :
* When using input type="number" the $parser pipeline of ngModel controller won't be able to access NaN values.
* For example : viewValue = '1e'  -> $parsers parameter value = "".
* This is because undefined values are not allowes by default (which can be changed, but better not do it)
* This makes it impossible to modify the view and model value; to get the view value, pop last character, apply to the view and return to the model.
*
* About the ngModel controller pipelines :
* view value -> $parsers -> model value
* model value -> $formatters -> view value
*
* About the $parsers pipeline :
* It is an array of functions executed in ascending order.
* When used with input type="number" :
* This array has 2 default functions, one of them transforms the datatype of the value from String to Number.
* To be able to change the value easier (substring), it is better to have access to a String rather than a Number.
* To access a String, the custom function added to the $parsers pipeline should be unshifted rather than pushed.
* Unshift gives the closest access to the view.
*
* About the $formatters pipeline :
* It is executed in descending order
* When used with input type="number"
* Default function transforms the value datatype from Number to String.
* To access a String, push to this pipeline. (push brings the function closest to the view value)
*
* The flow :
* When changing ngModel where the directive stands : (In this case only the view has to be changed. $parsers returns the changed model)
*     -When the value do not has to be modified :
*     $parsers -> $render();
*     -When the value has to be modified :
*     $parsers(view value) --(does view needs to be changed?) -> $render();
*       |                                  |
*       |                     $setViewValue(changedViewValue)
*       |                                  |
*       --<-------<---------<--------<------
*
* When changing ngModel where the directive does not stand :
*     - When the value does not has to be modified :
*       -$formatters(model value)-->-- view value
*     -When the value has to be changed
*       -$formatters(model vale)-->--(does the value has to be modified) -- (when loop $parsers loop is finished, return modified value)-->view value
*                                              |
*                                  $setViewValue(notChangedValue) giving back the non changed value allows the $parsers handle the 'bad' value
*                                               |                  and avoids it to think the value did not changed
*                Changed the model <----(the above $parsers loop occurs)
*
*/

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you may also want to remove the 0 at the beginning of the input... I simply add an if block to Mordred answer above because I cannot make a comment yet...

  app.directive('numericOnly', function() {
return {
require: 'ngModel',
link: function(scope, element, attrs, modelCtrl) {


modelCtrl.$parsers.push(function (inputValue) {
var transformedInput = inputValue ? inputValue.replace(/[^\d.-]/g,'') : null;


if (transformedInput!=inputValue) {
modelCtrl.$setViewValue(transformedInput);
modelCtrl.$render();
}
//clear beginning 0
if(transformedInput == 0){
modelCtrl.$setViewValue(null);
modelCtrl.$render();
}
return transformedInput;
});
}
};
})

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I ended up creating a modified directive of the above code to accept input and change the format on the fly...

.directive('numericOnly', function($filter) {
return {
require: 'ngModel',
link: function(scope, element, attrs, modelCtrl) {


element.bind('keyup', function (inputValue, e) {
var strinput = modelCtrl.$$rawModelValue;
//filter user input
var transformedInput = strinput ? strinput.replace(/[^,\d.-]/g,'') : null;
//remove trailing 0
if(transformedInput.charAt(0) <= '0'){
transformedInput = null;
modelCtrl.$setViewValue(transformedInput);
modelCtrl.$render();
}else{
var decimalSplit = transformedInput.split(".")
var intPart = decimalSplit[0];
var decPart = decimalSplit[1];
//remove previously formated number
intPart = intPart.replace(/,/g, "");
//split whole number into array of 3 digits
if(intPart.length > 3){
var intDiv = Math.floor(intPart.length / 3);
var strfraction = [];
var i = intDiv,
j = 3;


while(intDiv > 0){
strfraction[intDiv] = intPart.slice(intPart.length-j,intPart.length - (j - 3));
j=j+3;
intDiv--;
}
var k = j-3;
if((intPart.length-k) > 0){
strfraction[0] = intPart.slice(0,intPart.length-k);
}
}
//join arrays
if(strfraction == undefined){ return;}
var currencyformat = strfraction.join(',');
//check for leading comma
if(currencyformat.charAt(0)==','){
currencyformat = currencyformat.slice(1);
}


if(decPart ==  undefined){
modelCtrl.$setViewValue(currencyformat);
modelCtrl.$render();
return;
}else{
currencyformat = currencyformat + "." + decPart.slice(0,2);
modelCtrl.$setViewValue(currencyformat);
modelCtrl.$render();
}
}
});
}
};

})

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<input type="text" ng-model="employee.age" valid-input input-pattern="[^0-9]+" placeholder="Enter an age" />


<script>
var app = angular.module('app', []);


app.controller('dataCtrl', function($scope) {
});


app.directive('validInput', function() {
return {
require: '?ngModel',
scope: {
"inputPattern": '@'
},
link: function(scope, element, attrs, ngModelCtrl) {


var regexp = null;


if (scope.inputPattern !== undefined) {
regexp = new RegExp(scope.inputPattern, "g");
}


if(!ngModelCtrl) {
return;
}


ngModelCtrl.$parsers.push(function(val) {
if (regexp) {
var clean = val.replace(regexp, '');
if (val !== clean) {
ngModelCtrl.$setViewValue(clean);
ngModelCtrl.$render();
}
return clean;
}
else {
return val;
}


});


element.bind('keypress', function(event) {
if(event.keyCode === 32) {
event.preventDefault();
}
});
}
}}); </script>

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Basic HTML

<input type="number" />

Basic bootstrap

<input class="form-control" type="number" value="42" id="my-id">

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   <input type="text" name="profileChildCount" id="profileChildCount" ng-model="profile.ChildCount" numeric-only maxlength="1" />

you can use numeric-only attribute .

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Here is a pretty good solution to makes only allow enter number to the input:

<input type="text" ng-model="myText" name="inputName" onkeypress='return event.charCode >= 48 && event.charCode <= 57'/>

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None of the solutions proposed worked fine for me, and after a couple of hours I finally found the way.

This is the angular directive:

angular.module('app').directive('restrictTo', function() {
return {
restrict: 'A',
link: function (scope, element, attrs) {
var re = RegExp(attrs.restrictTo);
var exclude = /Backspace|Enter|Tab|Delete|Del|ArrowUp|Up|ArrowDown|Down|ArrowLeft|Left|ArrowRight|Right/;


element[0].addEventListener('keydown', function(event) {
if (!exclude.test(event.key) && !re.test(event.key)) {
event.preventDefault();
}
});
}
}
});

And the input would look like:

<input type="number" min="0" name="inputName" ng-model="myModel" restrict-to="[0-9]">

The regular expression evaluates the pressed key, not the value.

It also works perfectly with inputs type="number" because prevents from changing its value, so the key is never displayed and it does not mess with the model.

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DECIMAL

directive('decimal', function() {
return {
require: 'ngModel',
restrict: 'A',
link: function(scope, element, attr, ctrl) {
function inputValue(val) {
if (val) {
var digits = val.replace(/[^0-9.]/g, '');


if (digits.split('.').length > 2) {
digits = digits.substring(0, digits.length - 1);
}


if (digits !== val) {
ctrl.$setViewValue(digits);
ctrl.$render();
}
return parseFloat(digits);
}
return "";
}
ctrl.$parsers.push(inputValue);
}
};
});

DIGITS

directive('entero', function() {
return {
require: 'ngModel',
restrict: 'A',
link: function(scope, element, attr, ctrl) {
function inputValue(val) {
if (val) {
var value = val + ''; //convert to string
var digits = value.replace(/[^0-9]/g, '');


if (digits !== value) {
ctrl.$setViewValue(digits);
ctrl.$render();
}
return parseInt(digits);
}
return "";
}
ctrl.$parsers.push(inputValue);
}
};
});

angular directives for validate numbers

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Try this,

<input ng-keypress="validation($event)">


function validation(event) {
var theEvent = event || window.event;
var key = theEvent.keyCode || theEvent.which;
key = String.fromCharCode(key);
var regex = /[0-9]|\./;
if (!regex.test(key)) {
theEvent.returnValue = false;
if (theEvent.preventDefault) theEvent.preventDefault();
}


}

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All the above solutions are quite large, i wanted to give my 2 cents on this.

I am only checking if the value inputed is a number or not, and checking if it's not blank, that's all.

Here is the html:

<input type="text" ng-keypress="CheckNumber()"/>

Here is the JS:

$scope.CheckKey = function () {
if (isNaN(event.key) || event.key === ' ' || event.key === '') {
event.returnValue = '';
}
};

It's quite simple.

I belive this wont work on Paste tho, just so it's known.

For Paste, i think you would need to use the onChange event and parse the whole string, quite another beast the tamme. This is specific for typing.

UPDATE for Paste: just add this JS function:

$scope.CheckPaste = function () {
var paste = event.clipboardData.getData('text');


if (isNaN(paste)) {
event.preventDefault();
return false;
}
};

And the html input add the trigger:

<input type="text" ng-paste="CheckPaste()"/>

I hope this helps o/

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SOLUTION: I make a directive for all inputs, number, text, or any, in the app, so you can input a value and change the event. Make for angular 6

 import { Directive, ElementRef, HostListener, Input } from '@angular/core';


@Directive({
// tslint:disable-next-line:directive-selector
selector: 'input[inputType]'
})
export class InputTypeDirective {
constructor(private _el: ElementRef) {}


@Input() inputType: string;
// tipos: number, letter, cuit, tel


@HostListener('input', ['$event']) onInputChange(event) {
if (!event.data) {
return;
}


switch (this.inputType) {
case 'number': {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(/[^0-9]*/g, '');
if (initalValue !== this._el.nativeElement.value) {
event.stopPropagation();
}
break;
}
case 'text': {
const result = event.data.match(/[^a-zA-Z Ññ]*/g);
if (result[0] !== '') {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(
/[^a-zA-Z Ññ]*/g,
''
);
event.stopPropagation();
}
break;
}
case 'tel':
case 'cuit': {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(/[^0-9-]*/g, '');
if (initalValue !== this._el.nativeElement.value) {
event.stopPropagation();
}
}
}
}
}

HTML

     <input matInput inputType="number" [formControlName]="field.name" [maxlength]="field.length" [placeholder]="field.label | translate"  type="text" class="filter-input">