Prevent backspace from navigating back in AngularJS

问题

I faced this issue in my AngularJS webapp.

When a user enters a page with a form to fill and he starts typing, if he presses the backspace key and the focus is not on the input text, then the page goes to the previous state.

I looked up this solution using jQuery, but it doesn't seem the appropiate way for achieve this in AngularJS.

回答1:

There is $document in angular js:

angular.module('yourModule', [])
  .controller('yourController', ['$scope', '$document', function($scope, $document) {
      $document.on('keydown', function(e){
          if(e.which === 8 && ( e.target.nodeName !== "INPUT" && e.target.nodeName !== "SELECT" ) ){ // you can add others here inside brackets.
              e.preventDefault();
          }
      });

    }
  ]);

Plnkr Demo.

You can see in the demo i have used only for "INPUT" nodeName and it does not prevent the default of the backspace key on text input but not on textarea because we have not handled it in the condition.

回答2:

I can't comment "accepted answer", but it will work not right, as condition

e.which === 8 && e.target.nodeName !== "INPUT" || e.target.nodeName !== "SELECT"

with logic error, so you can use

e.which === 8 && e.target.nodeName !== "INPUT" && e.target.nodeName !== "SELECT"

or answer that wrote @ThisIsMarkSantiago.

回答3:

Add the below script in your controller

var rx = /INPUT|SELECT|TEXTAREA/i;

$document.on("keydown keypress", function(e){
    if( e.which == 8 ){ // 8 == backspace
        if(!rx.test(e.target.tagName) || e.target.disabled || e.target.readOnly ){
            e.preventDefault();
        }
    }
});

Or you can use Jquery

  $(function(){
      var regx = /INPUT|SELECT|TEXTAREA/i;

      $(document).bind("keydown keypress", function(e){
          if( e.which == 8 ){ // 8 == backspace
              if(!regx.test(e.target.tagName) || e.target.disabled || e.target.readOnly ){
                  e.preventDefault();
              }
          }
      });
  });

回答4:

I got this answer here: How can I disabling backspace key press on all browsers?

$(document).keydown(function(e) {
    var nodeName = e.target.nodeName.toLowerCase();

    if (e.which === 8) {
        if ((nodeName === 'input' && e.target.type === 'text') ||
            nodeName === 'textarea') {
            // do nothing
        } else {
            e.preventDefault();
        }
    }
});

Just put it inside your controller.

来源：https://stackoverflow.com/questions/29006000/prevent-backspace-from-navigating-back-in-angularjs

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javascript

jquery

angularjs

backspace