nz-upload组件上传文件,如何限制文件类型、文件大小等

原文链接:这里

0.前言

项目前端使用的组件是Ant Design。最近正好调试项目看到使用nz-uoload进行文件上传。但是要求限制文件上传的类型。这篇文章简单记录一下过程。

前台用的angular+Ant Design for Angular

1.HTML文件
<nz-upload [(nzFileList)]="fileList_product" [nzAccept]="fileType" [nzBeforeUpload]="beforeUploadProduct" [nzPreview]="handlePreview" [nzShowUploadList]="false" (nzChange)="handleChange($event)" style="float: right;"> <button nz-button nzType="primary"> <i class="anticon anticon-upload"></i><span>选择上传文件</span> </button> </nz-upload>

nzAccept 是可以接收的文件类型,

nzBeforeUpload 是再上传之前的文件检查,这是今天主要改动的地方

nzPreview 是预览文件方法

首先说下nzAccept,它表示上传的默认文件类型。在ts文件中可以参考下面的写法

  fileType: string = '.doc,docx,.pdf,rar,.xlsx,.xls'; //文件类型

但是,问题来了,这个只能保证你默认选的文件类型是上面这些,不能保证用户选择全部文件类型。如下图:

nz-upload组件上传文件,如何限制文件类型、文件大小等

可以看到,默认的文件类型确实是我们上面定义的哪些,但是如果用户在这个地方选择了所有文件,那么上面的文件类型限制就没用了。我们还是要想办法限制用户上传的文件类型。

2.限制文件类型的思路

主要说一下在前端限制上传文件类型的思路。一种是利用上传上来的文件类型直接判断(因为上面的操作无法限制上传的类型)。主要改动的地方是nzBeforeUpload方法。另外一种是判断文件的后缀。

先说第一种:

import { Component, OnInit, TemplateRef } from '@angular/core'; import { UploadFile, } from 'ng-zorro-antd'; import { Observable, Observer } from 'rxjs';   @Component({ selector: 'xxx', templateUrl: './xxx.component.html', styleUrls: ['./xxx.component.less'] }) export class AddComponent implements OnInit { constructor() { } ngOnInit() { } beforeUploadProduct = (file: UploadFile) => new Observable((observer: Observer<boolean>) => { const isType = file.type === 'image/jpeg' || file.type === 'image/png' || file.type === 'image/jpg' || file.type === 'image/gif'; debugger if (!isType) { console.log('只支持word、excel、pdf、rar类型!'); observer.complete(); return; } });   }

这里面的文件类型是固定的,可以参考下面的文件类型来使用:

office为 2007版本以后的一些 文件限制类型的 属性值

.xlsx   application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
.xltx   application/vnd.openxmlformats-officedocument.spreadsheetml.template
.potx   application/vnd.openxmlformats-officedocument.presentationml.template
.ppsx   application/vnd.openxmlformats-officedocument.presentationml.slideshow
.pptx   application/vnd.openxmlformats-officedocument.presentationml.presentation
.sldx   application/vnd.openxmlformats-officedocument.presentationml.slide
.docx   application/vnd.openxmlformats-officedocument.wordprocessingml.document
.dotx   application/vnd.openxmlformats-officedocument.wordprocessingml.template
.xlsm   application/vnd.ms-excel.addin.macroEnabled.12
.xlsb   application/vnd.ms-excel.sheet.binary.macroEnabled.12
.doc application/msword
.xls  application/vnd.ms-excel

其他的常用的:

.3gpp   audio/3gpp, video/3gpp  3GPP Audio/Video
*.ac3   audio/ac3   AC3 Audio
*.asf   allpication/vnd.ms-asf  Advanced Streaming Format
*.au    audio/basic AU Audio
*.css   text/css    Cascading Style Sheets
*.csv   text/csv    Comma Separated Values
*.doc   application/msword  MS Word Document
*.dot   application/msword  MS Word Template
*.dtd   application/xml-dtd Document Type Definition
*.dwg   image/vnd.dwg   AutoCAD Drawing Database
*.dxf   image/vnd.dxf   AutoCAD Drawing Interchange Format
*.gif   image/gif   Graphic Interchange Format
*.htm   text/html   HyperText Markup Language
*.html  text/html   HyperText Markup Language
*.jp2   image/jp2   JPEG-2000
*.jpe   image/jpeg  JPEG
*.jpeg  image/jpeg  JPEG
*.jpg   image/jpeg  JPEG
*.js    text/javascript, application/javascript JavaScript
*.json  application/json    JavaScript Object Notation
*.mp2   audio/mpeg, video/mpeg  MPEG Audio/Video Stream, Layer II
*.mp3   audio/mpeg  MPEG Audio Stream, Layer III
*.mp4   audio/mp4, video/mp4    MPEG-4 Audio/Video
*.mpeg  video/mpeg  MPEG Video Stream, Layer II
*.mpg   video/mpeg  MPEG Video Stream, Layer II
*.mpp   application/vnd.ms-project  MS Project Project
*.ogg   application/ogg, audio/ogg  Ogg Vorbis
*.pdf   application/pdf Portable Document Format
*.png   image/png   Portable Network Graphics
*.pot   application/vnd.ms-powerpoint   MS PowerPoint Template
*.pps   application/vnd.ms-powerpoint   MS PowerPoint Slideshow
*.ppt   application/vnd.ms-powerpoint   MS PowerPoint Presentation
*.rtf   application/rtf, text/rtf   Rich Text Format
*.svf   image/vnd.svf   Simple Vector Format
*.tif   image/tiff  Tagged Image Format File
*.tiff  image/tiff  Tagged Image Format File
*.txt   text/plain  Plain Text
*.wdb   application/vnd.ms-works    MS Works Database
*.wps   application/vnd.ms-works    Works Text Document
*.xhtml application/xhtml+xml   Extensible HyperText Markup Language
*.xlc   application/vnd.ms-excel    MS Excel Chart
*.xlm   application/vnd.ms-excel    MS Excel Macro
*.xls   application/vnd.ms-excel    MS Excel Spreadsheet
*.xlsm  application/vnd.ms-excel.sheet.macroEnabled.12
*.xlt   application/vnd.ms-excel    MS Excel Template
*.xlw   application/vnd.ms-excel    MS Excel Workspace
*.xml   text/xml, application/xml   Extensible Markup Language
*.zip   aplication/zip  Compressed Archive

第一种有个小问题,实际操作的时候,上传了一个rar文件,发现程序读不出来,然后放弃了第一种方法, 用第二种方法来写:

然后函数改成下面这样:

beforeUploadProduct = (file: UploadFile) => new Observable((observer: Observer<boolean>) => { //上传文件的后缀进行判断 const isType=[""] file.name.lastIndexOf(".") const fileType = file.name.substring(file.name.lastIndexOf("."),file.name.length) //从后往前截取文类型 if(fileType==".doc"||fileType==".docx"||fileType==".pdf"||fileType==".rar"||fileType==".xlsx"||fileType==".xls"){ observer.next(true); observer.complete(); }else{ console.log('只支持word、excel、pdf、rar类型!'); observer.complete(); return; } });
3.限制文件大小

参考代码如下:

beforeUploadProduct = (file: UploadFile) => new Observable((observer: Observer<boolean>) => {   const isLt2M = file.size! / 1024 / 1024 < 2; if (!isLt2M) { console.log('图片大小不要超过2MB!'); observer.complete(); return; } });

我们读取出来文件的大小,直接判断就行。

 

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