Question

我不理解以下内容。也许我在这里错过了一些非常愚蠢的问题...有人可以解决吗？预先感谢。

我在Javascript中有以下代码：

Calling Extraction
Service List Size: 1
Identified Ethernet Link: 
Path: /net/connman/service/ethernet_0800277d326e_cable
        Type: ethernet
        Sate: ready
        Favorite: 0
        Auto Connect: 0
        Name: Wired
        Net Mode: manual
        Iface: eth0
        Mac: 08:00:27:7D:32:6E
        IP Address: 10.0.2.15
        Net Mask: 255.255.255.0
on_manager_properties_changed
children: 139764141513856
on_manager_properties_changed
children: 145

它就像一个护身符，因此，如果我更改document.getElementById ...并放上

signal time=1549641357.679460 sender=:1.3 -> destination=(null destination) serial=488 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "State"
   variant       string "ready"
signal time=1549641357.680844 sender=:1.3 -> destination=(null destination) serial=489 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "Nameservers"
   variant       array [
         string "10.0.2.3"
      ]
signal time=1549641357.681186 sender=:1.3 -> destination=(null destination) serial=490 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "Domains"
   variant       array [
      ]
signal time=1549641357.681601 sender=:1.3 -> destination=(null destination) serial=491 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "Proxy"
   variant       array [
         dict entry(
            string "Method"
            variant                string "direct"
         )
      ]
signal time=1549641357.681780 sender=:1.3 -> destination=(null destination) serial=492 path=/net/connman/technology/ethernet; interface=net.connman.Technology; member=PropertyChanged
   string "Connected"
   variant       boolean true
signal time=1549641357.682210 sender=:1.3 -> destination=(null destination) serial=493 path=/; interface=net.connman.Manager; member=PropertyChanged
   string "State"
   variant       string "ready"
signal time=1549641357.696004 sender=:1.3 -> destination=(null destination) serial=494 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "IPv4"
   variant       array [
         dict entry(
            string "Method"
            variant                string "dhcp"
         )
      ]
signal time=1549641357.696227 sender=:1.3 -> destination=(null destination) serial=495 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "IPv4"
   variant       array [
         dict entry(
            string "Method"
            variant                string "dhcp"
         )
         dict entry(
            string "Address"
            variant                string "10.0.2.15"
         )
         dict entry(
            string "Netmask"
            variant                string "255.255.255.0"
         )
      ]
signal time=1549641357.696454 sender=:1.3 -> destination=(null destination) serial=496 path=/net/connman/service/ethernet_0800277d326e_cable; interface=net.connman.Service; member=PropertyChanged
   string "IPv4"
   variant       array [
         dict entry(
            string "Method"
            variant                string "dhcp"
         )
         dict entry(
            string "Address"
            variant                string "10.0.2.15"
         )
         dict entry(
            string "Netmask"
            variant                string "255.255.255.0"
         )
         dict entry(
            string "Gateway"
            variant                string "10.0.2.2"
         )
      ]

它也可以正常工作...但是，如果我放置“ return”，该函数将返回 undefined 变量内容。像这样：

function funcLeNrPaginasPDF(strCaminhoPDF) {
    var objLivrariaPDF = window['pdfjs-dist/build/pdf'];
    var objDocumentoPDF = null; 

    objLivrariaPDF.workerSrc = '/pdfjs/pdf.worker.js';

    // strCaminhoPDF var contains the pdf doc: "documento.pdf"

    var oprCarregaPDF = objLivrariaPDF.getDocument(strCaminhoPDF);
    oprCarregaPDF.promise.then(function(objDocumentoPDF) { document.getElementById('nr_paginas').textContent = objDocumentoPDF.numPages; });

有什么想法吗？我需要一个变量来保存页面数。问候。

Answer 1

解决了。对于这种不重要且容易发现的故障感到愧。返回必须放在内部函数的括号之外……ahmen。

使用PDF.JS检索PDF的页面数失败并返回

1 个答案: