ng-pattern with regex having double quotes does no

I have a ng-pattern validation for a regex of ^[^\./:*\?\"<>\|]{1}[^\/:*\?\"<>\|]{0,254}$ which basically tests the invalid chars in filepath and teh limit. but when i have the ng-pattern specified as

 ng-pattern = "^[^\\\./:\*\?\"<>\|]{1}[^\\/:\*\?\"<>\|]{0,254}$"

, the ng-pattern shows the regex in an incorrect way. any help on achieving this correctly

回答1:

First of all, your regex contains too many escaping symbols, while you only need to escape the " here and \\.

Then, to match a " inside ng-pattern attribute, you may define it as \x22 or ":

var app = angular.module("app", []);

<html ng-app="app">
<head>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
</head>
<body>
<form name="form">
  <p>Enter text to validate:</p>
  <input type="text" ng-model="name" name="name" ng-pattern="/^[^\\\\./:*?&quot;<>|][^\\\\/:*?\x22<>|]{0,254}$/" ng-trim="false" />
  <div ng-show="form.name.$error.pattern">Text doesn't match with ng-pattern!</div>
</form>
</body>
</html>

You may also solve the problem by defining a regex in the controller with a regular string literal where you may use '.."..' or "..\"...", and then use the variable name inside {{...}} in the ng-pattern attribute. Note that to match a literal \ you need to use 4 backslashes in the regex pattern.

var app = angular.module("app",[]);

app.controller("FormCtrl", function($scope) {
  $scope.regex = "/^[^\\\\./:*?\"<>|][^\\\\/:*?\"<>|]{0,254}$/";
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="app">
    <form name="theForm" ng-controller="FormCtrl" novalidate>
        <input type="text" name="filename" placholder="filename" ng-model="filename" ng-pattern="{{regex}}" required />
        <div class="error"
                     ng-show="(theForm.filename.$dirty || attempted) && theForm.filename.$invalid">
                  <small class="error text-danger"
                         ng-show="theForm.filename.$error.required">
                    Please enter a file name.
                  </small>
                  <small class="error text-danger"
                         ng-show="theForm.filename.$error.pattern">
                    Please enter a valid file name.
                  </small>
                </div>
    </form>
</div>

回答2:

I was trying to exclude ' and " in a ng-pattern which is similar to the problem above. I found a way to embed ' or " directly without having to use a scope variable:

<input type="text" ng-pattern="/^[^&#34&#39]+$/" />

回答3:

You can use \" to escape ".