如何将输入限制为仅接受数字？

Question

我在AngularJS中使用ngChange触发一个自定义函数，该函数将删除用户添加到输入中的任何字母。

<input type="text" name="inputName" data-ng-change="numbersOnly()"/>

问题是我需要定位触发numbersOnly()的输入，以便我可以删除输入的字母。我在Google上看了很长时间，并且无法找到任何相关内容。

我该怎么办？

Answer 1

简单方法，如果适用于您的用例，请使用type="number"：

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

另一种简单方法： ng-pattern也可用于定义将限制字段中允许的内容的正则表达式。另请参阅"cookbook" page about forms。

<强>的hackish？方式，$在你的控制器中观察ng-model：

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

控制器：

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

最佳方式，在指令中使用$ parser。 我不打算重复@ pkozlowski.opensource提供的已经很好的答案，所以这里是链接：https://stackoverflow.com/a/14425022/215945

所有上述解决方案都涉及使用ng-model，这使得找不到this。

使用ng-change会导致问题。见AngularJS - reset of $scope.value doesn't change value in template (random behavior)

Answer 2

在文字字段中使用ng-pattern：

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

然后将其包含在您的控制器上

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

Answer 3

所提出的解决方案都没有对我有用，几个小时后我终于找到了方法。

这是角度指令：

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();
                }
            });
        }
    }
});

输入看起来像：

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

正则表达式评估按下的键，而不是值。

它也可以与输入type="number"完美配合，因为它可以防止更改其值，因此密钥永远不会显示，也不会影响模型。

Answer 4

这是我对@Mark Rajcok推荐的$parser解决方案的最佳实施方法。它本质上是@ pkozlowski.opensource的excellent $parser for text answer但重写只允许数字。所有的功劳归功于他，这只是为了节省你5分钟阅读答案，然后重写你自己：

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;
            });
        }
    };
});

你可以这样使用它：

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

有趣的是，空格永远不会到达解析器，除非被字母数字所包围，因此您必须根据需要.trim()。此外，此解析器对<input type="number">执行 NOT 工作。出于某种原因，非数字不会将它移到解除器的位置，但是它们做使它成为输入控件本身。

Answer 5

有几种方法可以做到这一点。

您可以使用 class RecyclerTouchListener implements RecyclerView.OnItemTouchListener { //to intercept touch before RecyclerView picks up ACTION_UP or ACTION_DOWN public ClickListener clickListener; private GestureDetector gestureDetector; public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) { this.clickListener=clickListener; gestureDetector=new GestureDetector(context,new GestureDetector.SimpleOnGestureListener(){ @Override public boolean onSingleTapUp(MotionEvent e) { return true; } @Override public void onLongPress(MotionEvent e) { View child=recyclerView.findChildViewUnder(e.getX(),e.getY()); if(child!=null&&clickListener!=null){ clickListener.onLongClick(child,recyclerView.getChildAdapterPosition(child)); } } }); } @Override public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) { View child=rv.findChildViewUnder(e.getX(),e.getY()); if (child!=null&&clickListener!=null&&gestureDetector.onTouchEvent(e)){ clickListener.onClick(child,rv.getChildAdapterPosition(child)); } return false; } @Override public void onTouchEvent(RecyclerView rv, MotionEvent e) { } @Override public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { } } public static interface ClickListener { //Interface to detect touch public void onClick(View v, int position); public void onLongClick(View v, int position); } ：

type="number"

或者 - 我为此创建了一个可重用的directive，它使用正则表达式。

<强> HTML

<input type="number" />

<强>的Javascript

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

Answer 6

这是一个Plunker处理任何上述命题无法处理的情况 通过使用$ formatters和$ parsers管道并避免使用type =“number”

以下是问题/解决方案的解释（也可在Plunker中找到）：

/*
 *
 * 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)
 *
 */

Answer 7

以上所有解决方案都很大，我想为此付出2美分。

我只检查输入的值是否为数字，并检查输入的值是否为空。

这是html：

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

这是JS：

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

这很简单。

我相信这不会对Paste tho起作用，就这样就知道了。

对于粘贴，我认为您将需要使用onChange事件并解析整个字符串，这是另一种猛兽。这是专门用于键入的。

粘贴更新：只需添加此JS函数：

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

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

然后html输入添加触发器：

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

我希望这对o /

有帮助

Answer 8

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

Answer 9

解决方案： 我在应用程序中为所有输入，数字，文本或任何内容制定了一条指令，因此您可以输入一个值并更改事件。 制作角度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">

Answer 10

尝试一下

<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();
    }

}

Answer 11

这是一个非常好的解决方案，只允许输入input的数字：

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

Answer 12

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

您可以使用仅限数字的属性。

Answer 13

基本和干净的HTML方式

SELECT * FROM sys.fn_my_permissions('TEST', 'USER');

Answer 14

您可能还想删除输入开头的0 ...我只是在上面的Mordred回答中添加了一个if块，因为我还无法发表评论......

({ function() { alert("Hello") } })

Answer 15

我知道这是旧的，但我已经为此目的创建了一个指令，以防任何人寻找一个简单的解决方案。使用起来非常简单。

您可以查看here。

Answer 16

<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>

Answer 17

我最终创建了上述代码的修改指令，以接受输入并动态更改格式......

.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();
                 }
             }
            });
      }
  };

}）