是这样的:

{{ data.title | slice:0:20 }}

如果你想要省略号，这里有一个变通方法

{{ data.title | slice:0:20 }}...

我一直在使用这个模块ng2 truncate，它很简单，导入模块和u已经准备好了…在{{data。标题| truncate: 20}}

刚刚尝试了@蒂莫西佩雷斯的回答，并添加了一行

if (value.length < limit)
   return `${value.substr(0, limit)}`;

to

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'truncate'
})
export class TruncatePipe implements PipeTransform {
transform(value: string, limit = 25, completeWords = false, ellipsis = '...') {

   if (value.length < limit)
   return `${value.substr(0, limit)}`;

   if (completeWords) {
     limit = value.substr(0, limit).lastIndexOf(' ');
   }
   return `${value.substr(0, limit)}${ellipsis}`;
}
}

您可以根据CSS截断文本。它有助于根据宽度截断文本，而不是固定字符。

例子

CSS

.truncate {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.content {
    width:100%;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

HTML

<div class="content">
    <span class="truncate">Lorem Ipsum is simply dummied text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.</span>
</div>

注意:这段代码一行使用full，而不是多行。

如果你想用Angular来做，那么Ketan的解决方案是最好的

下面是另一种方法，使用接口来描述要通过标记中的管道传递的选项对象的形状。

@Pipe({
  name: 'textContentTruncate'
})
export class TextContentTruncatePipe implements PipeTransform {

  transform(textContent: string, options: TextTruncateOptions): string {
    if (textContent.length >= options.sliceEnd) {
      let truncatedText = textContent.slice(options.sliceStart, options.sliceEnd);
      if (options.prepend) { truncatedText = `${options.prepend}${truncatedText}`; }
      if (options.append) { truncatedText = `${truncatedText}${options.append}`; }
      return truncatedText;
    }
    return textContent;
  }

}

interface TextTruncateOptions {
  sliceStart: number;
  sliceEnd: number;
  prepend?: string;
  append?: string;
}

然后在你的标记中:

{{someText | textContentTruncate:{sliceStart: 0, sliceEnd: 50, append: '...'} }}

为了获得更多的灵活性，如果我们想从结尾或开始截断(基于@Nika Kasradze):

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'truncate'
})
export class TruncatePipe implements PipeTransform {

  transform(value: string, args: any[]): string {
    const limit = args.length > 0 ? parseInt(args[1], 10) : 20;
    const trail = args.length > 1 ? args[3] : '...';
    return value.length > limit ? (args[2] === 'start' ? trail : '') + value.substr(args[0], limit) + (args[2] === 'end' ? trail : '') : value;
   }
}

如何使用?

{{ myLongText | truncate:[20, myLongText.length-20, 'start', '...'] }}