AngularJS ng-pattern指令

AngularJS中的ng-pattern指令是用来在输入的HTML元素上为ngModel添加模式（regex模式）验证器。如果输入字段数据与ngpattern属性值中指定的Angular表达式不匹配，它被用来设置模式验证错误键。

语法:

<element ng-pattern="expression"> Contents... </element>

例子1：这个例子使用ng-pattern指令来检查密码模式。

<!DOCTYPE html>
<html>
  
<head>
    <title>ng-pattern Directive</title>
      
    <script src=
"https://ajax.googleapis.com/ajax/libs/angularjs/1.4.2/angular.min.js">
    </script> 
      
    <style>
        .red {
            color:red
        }
        .green {
            color:green
        }
    </style>
</head>
  
<body ng-app="app" style="text-align:center">
      
    <h1 style="color:green;">GeeksforGeeks</h1>
    <h2 style="">ng-pattern Directive</h2>
  
    <div ng-controller="geek">
        <ng-form name="pass">
            Password:<input type="password" ng-model="password"
                name="password" ng-pattern="re" /><br>
                  
            <span ng-show="pass.password.error.pattern" 
                    style="color:red">
                Not valid password.
            </span><br>
              
            Confirm: <input type="password" ng-model="repass"
                    ng-keyup="compare(repass)" name="repass"
                    ng-pattern="re" /><br>
              
            <span ng-show="isconfirm || pass.repass.dirty "
                ng-class="{true:'green',false:'red'}[isconfirm]">
                Password {{isconfirm==true?'':'not'}} match
            </span>
        </ng-form>
    </div>
      
    <script>
        var app = angular.module("app", []);
        app.controller('geek', ['scope', function (scope) {
            scope.re = /^[a-zA-Z]\w{3,14}/;
              
            scope.compare = function (repass) {
                scope.isconfirm = $scope.password == repass ?
                        true : false;
            }
        }]);
    </script>
</body>
  
</html>

输出:

Invalid Input:
输入不匹配。
Valid Input:

例子2：如果输入的不是数字，这个例子会显示错误。

<!DOCTYPE html>
<html>
  
<head>
    <title>ng-pattern Directive</title>
      
    <script src=
"https://ajax.googleapis.com/ajax/libs/angularjs/1.4.2/angular.min.js">
    </script> 
</head>
  
<body ng-app="app" style="text-align:center">
      
    <h1 style="color:green;">GeeksforGeeks</h1>
    <h2 style="">ng-pattern Directive</h2>
  
    <div ng-controller="geek">
        <ng-form name="num">
            Input Number: <input type="text" ng-model="number"
                name="number" ng-pattern="re" /><br />
              
            <span ng-show="num.number.error.pattern" style="color:red">
                Input is not valid.
            </span>
        </ng-form>
    </div>
      
    <script>
        var app = angular.module("app", []);
          
        app.controller('geek', ['scope', function (scope) {
            scope.re = /^[0-9]{1,6}$/;
        }]);
    </script>
</body>
  
</html>