Javascript 类型错误：无法读取未定义的属性“concat”
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TypeError: Cannot read property 'concat' of undefined
提问by ninjaXnado
My problem is that when i run my project it gives me an error that says: TypeError: Cannot read property 'concat' of undefined. it does not display please help.
我的问题是，当我运行我的项目时，它给了我一个错误：类型错误：无法读取未定义的属性“concat”。它不显示请帮助。
app.js
应用程序.js
var Call24 = angular.module("Call24", ["ngResource", "ngRoute"]).
config(function($routeProvider) {
$routeProvider.
when('/', { controller: ListCtrl, templateUrl: 'CycleModal.html' }).
when('/edit/:editId', { controller: EditCtrl, templateUrl: 'details.html' }).
otherwise({ redirectTo: '/' });
Call24.factory('cyclesFactory', function ($resource) {
return $resource('/api/Cycles/:id', { id3: '@id3' }, { update: 'PUT' });
});
var ListCtrl = function ($scope, $location, data,$http) {
$scope.selectTest = null;
$scope.testTest = [];
$scope.cycle = [];
$http({
method: 'GET',
url: '/api/Cycles/',
data: { CycleID: 1 }
}).success(function (result) {
$scope.testTest = result;
});
$scope.search = function() {
data.query({
offset: $scope.offset,
limit: $scope.limit
},
function(something) {
$scope.cycle = $scope.cycle.concat(something);
});
};
$scope.search();
$scope.show_more = function() {
$scope.offset += $scope.limit;
$scope.search();
};
$scope.reset = function () {
$scope.limit = 4;
$scope.offset = 0;
$scope.cycle = [];
$scope.search();
}
};
html
html
Weeks in Cycle
周期中的周数
<div class="col-sm-3">
<div class="form-group">
<div class="input-group input-group-addon">
<label>Cycle number</label>
<input ng-model="query" class="form-control" placeholder="search rep">
<!--<div class="input-group-btn">
<button ng-click="reset()" class="btn btn-default" type="submit"><i class="glyphicon glyphicon-search"></i></button>
</div>-->
</div>
</div>
</div>
<div class="col-sm-1">
<div class="form-group">
<div class="input-group input-group-addon">
<!--<label>Rep</label>
<input ng-model="part" class="form-control" placeholder="search rep">-->
<div class="input-group-btn">
<button ng-click="reset()" class="btn btn-default" type="submit"><i class="glyphicon glyphicon-search"></i></button>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</form>
<table class="table table-striped table-condensed table-bordered">
<thead>
<th>Cycle Id</th>
<th>Weeks In Cycle</th>
<th>Cycle Number</th>
<th>Start Date</th>
<th>End Date</th>
</thead>
<tbody>
<tr ng-repeat="liss in cycle">
<td>{{liss.CycleID}}</td>
<td>{{liss.WeeksInCycle}}</td>
<td>{{liss.Cycle}}</td>
<td>{{liss.StartDate}}</td>
<td>{{liss.EndDate}}</td>
</tr>
</tbody>
</table>
<div class="form-actions">
<button class="btn btn-primary" ng-click="updateSurvey()">
Ok
</button>
<button class="btn btn-danger">
<a href="#/index.html" style="color: white; text-decoration: none">Cancel</a>
</button>
</div>
I want to display the list from a table but it keeps giving the error i have shown above.
我想显示表格中的列表，但它不断给出我上面显示的错误。
回答by dhavalcengg
Because $scope.cycle is not initialized
因为 $scope.cycle 没有初始化
$scope.cycle = '' or $scope.cycle= [] // as per your requirement
回答by Kalhan.Toress
seems like you didn't declare the $scope.cyclebefore its use, javascript try to invoke concat()of $scope.cyclevariable but still there is no variable called $scope.cycle. so invoking concat()of a undefined variable cause a error.
好像你没有声明$scope.cycle其使用之前，JavaScript的尝试调用concat()的$scope.cycle变量，但仍然没有所谓的变量$scope.cycle。因此调用concat()未定义的变量会导致错误。
if you try to concat two arrays then
如果您尝试连接两个数组，则
try to add $scope.cycle = []top of the controller
尝试添加$scope.cycle = []控制器的顶部
if you try to concat two Strings then
如果您尝试连接两个字符串，则
try to add $scope.cycle = ''top of the controller
尝试添加$scope.cycle = ''控制器的顶部
