angular中为什么会使用track by 实现ng-repeat嵌套

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slides是一个二维数组,我以上的代码会报错Error: [ngRepeat:dupes]


<div ng-repeat="links in slides"><div ng-repeat="link in links track by $index">{{link.name}}</div> </div> $http.get('index.PHP?option=com_mtree&task=ajax.load').success(function(response) { if(response.status) { $scope.links = response.links; if(typeof response.links != 'undefined') { var slides = [],slide; for(var i=0; i<response.links.length;) { slide = []; var c=0; c<3&&c<response.links.length; c++,i++) { slide.push(response.links.indexOf(i)); } slides.push(slide); } $scope.slides = slides; } /* setTimeout(function(){ jQuery('.saved-list .slideshow').cycle('destroy'); jQuery('.saved-list .slideshow').cycle(); },0); */ } });

Error: [ngRepeat:dupes]这个出错提示具体到题主的情况,意思是指数组中有2个以上的相同数字。ngRepeat不允许collection中存在两个相同Id的对象

For example:item in itemsis equivalent toitem in items track by $id(item). This implies that the DOM elements will be associated by item identity in the array.

对于数字对象来说,它的id就是它自身的值,因此,数组中是不允许存在两个相同的数字的。为了规避这个错误,需要定义自己的track by表达式。例如:item in items track by item.id或者item in items track by fnCustomId(item)。嫌麻烦的话,直接拿循环的索引变量$index来用item in items track by $index

ngRepeat不允许collection中存在两个相同Id的对象

For example:item in items track by $id(item). This implies that the DOM elements will be associated by item identity in the array.

item in items track by $index

原文链接:https://www.f2er.com/angularjs/149706.html

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