分类:常见Bug

  • How to position two divs horizontally within another div

    Its quite a common misconception that you need a clear:both div at the bottom, when you really don't. While foxy's answer is correct, you don't need that non-semantic, useless clearing div. All you ne...

    10 分钟前
  • Cannot access Inputs from my controller/constructor

    Because the Input property isn't initialized until view is set up. According to the docs, you can access your data in ngOnInit method. import {Component, bootstrap, Input, OnInit} from '@angular/co...

    15 分钟前
  • What is .$on() in AngularJS

    $on is related to $broadcast and $emit - which is a way to trigger code from other places. The first thing about $on you should know is that it's a method of $scope The second thing you should know ...

    20 分钟前
  • Center an element in Bootstrap 4 Navbar

    In Bootstrap 4, there is a new utility known as .mx-auto. You just need to specify the width of the centered element. Ref: http://v4-alpha.getbootstrap.com/utilities/spacing/#horizontal-centering Di...

    25 分钟前
  • MongoDB collection hyphenated name

    Use this syntax: db['repl-failOver'].find({}) or db.getCollection('repl-failOver').find({}) You can find more information in the Executing Queries section of the manual: If the mongo shell d...

    30 分钟前
  • Shell: redirect stdout to /dev/null and stderr to stdout [duplicate]

    You want ./script 2>&1 1>/dev/null | ./other-script The order here is important. Let's assume stdin (fd 0), stdout (fd 1) and stderr (fd 2) are all connected to a tty initially, so 0:...

    40 分钟前
  • NuGet error on creating MVC4 Project in VS 2012

    I believe you do not have NuGet Package Manager extension installed. If not, you can click TOOLS -> Extensions and Updates... -> Online, select NuGet Package Manager, and click Download: ...

    1 小时前
  • Why write 'at' and 'dot' in email rather than '@' and '.'? [closed]

    Typically people do this to avoid having their email addresses found by spambots that search for a regex that matches email address formatting. By using _AT_ and _DOT_, the symbols that the spambot i...

    1 小时前
  • How to specify 64 bit integers in c

    Use stdint.h for specific sizes of integer data types, and also use appropriate suffixes for integer literal constants, e.g.: #include <stdint.h> int64_t i2 = 0x0000444400004444LL; ...

    1 小时前
  • MongoDB: unconditional updates?

    The error says it all: You can only modify multiple documents using the $ modifier operators. You probably had something like this: > db.coll.update({ }, { a: 'b' }, false, true); Which would no...

    1 小时前
  • Is it safe to replace '==' with 'is' to compare Boolean-values

    You probably shouldn't ever need to compare booleans. If you are doing something like: if some_bool == True: ... ...just change it to: if some_bool: ... No is or == needed. As commenters ha...

    1 小时前
  • Spring MVC “redirect:” prefix always redirects to http — how do I make it stay on https?

    The short answer is, set the InternalResourceViewResolver's redirectHttp10Compatible property to false: <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewRe...

    1 小时前
  • Mac command line tools 11.4 no longer has svn

    macOS Catalina I had the same issue after upgrading to Catalina 10.15. It's clearly mentioned in the Apple website that SVN is deprecated in Xcode 11: You can find it here: https://developer.apple.com...

    1 小时前
  • ngIf - Expression has changed after it was checked

    this error occur because you in dev mode: In dev mode change detection adds an additional turn after every regular change detection run to check if the model has changed. so, to force change detecti...

    1 小时前
  • Does SqlCommand.Dispose close the connection?

    No, Disposing of the SqlCommand will not effect the Connection. A better approach would be to also wrap the SqlConnection in a using block as well: using (SqlConnection conn = new SqlConnection(c...

    1 小时前
  • View log files of crashed pods in kubernetes

    Assuming that your pod still exists: kubectl logs <podname> --previous $ kubectl logs -h -p, --previous[=false]: If true, print the logs for the previous instance of the container in a pod if i...

    2 小时前
  • Vue JS 2.0 not rendering anything?

    Just to make life easier for folks looking for the answer: import Vue from 'vue/dist/vue.js' import App from './App.vue' new Vue({ el: '#app', render: h => h(App) }) From the author -- 2.0...

    2 小时前
  • How can set two primary key fields for my models in Django

    I would implement this slightly differently. I would use a default primary key (auto field), and use the meta class property, unique_together class Hop(models.Model): migration = models.Forei...

    2 小时前
  • PHP check if file is an image [duplicate]

    Native way to get the mimetype: For PHP < 5.3 use mime_content_type() For PHP >= 5.3 use finfo_open() or mime_content_type() Alternatives to get the MimeType are exif_imagetype and getimagesiz...

    2 小时前
  • when is smart to use bindService and when startService

    You usually use bindService() if your calling component(Activity) will need to communicate with the Service that you are starting, through the ServiceConnection. If you do not want to communicate with...

    2 小时前