我有以下几点:
<div>{{modal.title}}</div>
有没有一种方法可以限制字符串的长度,比如20个字符?
一个更好的问题是,有没有一种方法可以将字符串更改为截断并显示。如果超过20个字符?
我有以下几点:
<div>{{modal.title}}</div>
有没有一种方法可以限制字符串的长度,比如20个字符?
一个更好的问题是,有没有一种方法可以将字符串更改为截断并显示。如果超过20个字符?
当前回答
下面是一个用于截断文本的自定义过滤器。它的灵感来自于EpokK的解决方案,但根据我的需求和口味进行了修改。
angular.module('app').filter('truncate', function () {
return function (content, maxCharacters) {
if (content == null) return "";
content = "" + content;
content = content.trim();
if (content.length <= maxCharacters) return content;
content = content.substring(0, maxCharacters);
var lastSpace = content.lastIndexOf(" ");
if (lastSpace > -1) content = content.substr(0, lastSpace);
return content + '...';
};
});
这里是单元测试,所以你可以看到它应该如何表现:
describe('truncate filter', function () {
var truncate,
unfiltered = " one two three four ";
beforeEach(function () {
module('app');
inject(function ($filter) {
truncate = $filter('truncate');
});
});
it('should be defined', function () {
expect(truncate).to.be.ok;
});
it('should return an object', function () {
expect(truncate(unfiltered, 0)).to.be.ok;
});
it('should remove leading and trailing whitespace', function () {
expect(truncate(unfiltered, 100)).to.equal("one two three four");
});
it('should truncate to length and add an ellipsis', function () {
expect(truncate(unfiltered, 3)).to.equal("one...");
});
it('should round to word boundaries', function () {
expect(truncate(unfiltered, 10)).to.equal("one two...");
});
it('should split a word to avoid returning an empty string', function () {
expect(truncate(unfiltered, 2)).to.equal("on...");
});
it('should tolerate non string inputs', function () {
expect(truncate(434578932, 4)).to.equal("4345...");
});
it('should tolerate falsey inputs', function () {
expect(truncate(0, 4)).to.equal("0");
expect(truncate(false, 4)).to.equal("fals...");
});
});
其他回答
我创建了这个指令,很容易做到这一点,截断字符串到指定的限制,并添加了一个“显示更多/更少”切换。你可以在GitHub上找到它:https://github.com/doukasd/AngularJS-Components
它可以这样使用:
<p data-dd-collapse-text="100">{{veryLongText}}</p>
下面是指令:
// a directive to auto-collapse long text
app.directive('ddCollapseText', ['$compile', function($compile) {
return {
restrict: 'A',
replace: true,
link: function(scope, element, attrs) {
// start collapsed
scope.collapsed = false;
// create the function to toggle the collapse
scope.toggle = function() {
scope.collapsed = !scope.collapsed;
};
// get the value of the dd-collapse-text attribute
attrs.$observe('ddCollapseText', function(maxLength) {
// get the contents of the element
var text = element.text();
if (text.length > maxLength) {
// split the text in two parts, the first always showing
var firstPart = String(text).substring(0, maxLength);
var secondPart = String(text).substring(maxLength, text.length);
// create some new html elements to hold the separate info
var firstSpan = $compile('<span>' + firstPart + '</span>')(scope);
var secondSpan = $compile('<span ng-if="collapsed">' + secondPart + '</span>')(scope);
var moreIndicatorSpan = $compile('<span ng-if="!collapsed">...</span>')(scope);
var toggleButton = $compile('<span class="collapse-text-toggle" ng-click="toggle()">{{collapsed ? "less" : "more"}}</span>')(scope);
// remove the current contents of the element
// and add the new ones we created
element.empty();
element.append(firstSpan);
element.append(secondSpan);
element.append(moreIndicatorSpan);
element.append(toggleButton);
}
});
}
};
}]);
和一些CSS去它:
.collapse-text-toggle {
font-size: 0.9em;
color: #666666;
cursor: pointer;
}
.collapse-text-toggle:hover {
color: #222222;
}
.collapse-text-toggle:before {
content: '\00a0(';
}
.collapse-text-toggle:after {
content: ')';
}
你可以简单地在div中添加一个css类,并通过angularjs添加一个工具提示,这样鼠标移过去时就可以看到修剪后的文本。
< div class = " trim-info“工具提示= " {{modal.title}} > {{modal.title}} < / div > .trim-info { max-width: 50 px; 显示:inline-block; 溢出:隐藏; 文本溢出:省略; 空白:nowrap;} 行高:15 px; 位置:相对; }
Use this in your html - {{value | limitTocustom:30 }}
and write this custom filter in your angular file,
app.filter('limitTocustom', function() {
'use strict';
return function(input, limit) {
if (input) {
if (limit > input.length) {
return input.slice(0, limit);
} else {
return input.slice(0, limit) + '...';
}
}
};
});
// if you initiate app name by variable app. eg: var app = angular.module('appname',[])
我也遇到过类似的问题,我是这样做的:
{{ longString | limitTo: 20 }} {{longString.length < 20 ? '' : '...'}}
在html中,它与angular自身提供的limitTo过滤器一起使用,如下所示:
<p> {{limitTo:30 | keepDots }} </p>
filter keepDots:
App.filter('keepDots' , keepDots)
function keepDots() {
return function(input,scope) {
if(!input) return;
if(input.length > 20)
return input+'...';
else
return input;
}
}