大约有 42,000 项符合查询结果（耗时：0.0434秒） [XML]
Why do we use Base64?
...When you encode text in ASCII, you start with a text string and convert it to a sequence of bytes.
When you encode data in Base64, you start with a sequence of bytes and convert it to a text string.
To understand why Base64 was necessary in the first place we need a little history of computing.
...
How to force garbage collector to run?
Interviewer asked me about this today ...is there an answer ?
7 Answers
7
...
How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
...
Assuming you've used home-brew to install and upgrade Postgres, you can perform the following steps.
Stop current Postgres server:
launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Initialize a new 10.1 database:
initdb /usr/local/...
How to resize superview to fit all subviews with autolayout?
My understanding of autolayout is that it takes the size of superview and base on constrains and intrinsic sizes it calculates positions of subviews.
...
Mutable vs immutable objects
I'm trying to get my head around mutable vs immutable objects. Using mutable objects gets a lot of bad press (e.g. returning an array of strings from a method) but I'm having trouble understanding what the negative impacts are of this. What are the best practices around using mutable objects? Should...
No == operator found while comparing structs in C++
...
In C++, structs do not have a comparison operator generated by default. You need to write your own:
bool operator==(const MyStruct1& lhs, const MyStruct1& rhs)
{
return /* your comparison code goes here */
}
...
Hosting a Maven repository on github
...k of a small open sourced library that I'm working on on github. I'd like to make it available to other developers via maven, but I don't want to run my own Nexus server, and because it's a fork I can't easily deploy it to oss.sonatype.org.
...
Refresh image with a new one at the same url
...e.jpg?" + new Date().getTime();
This will append the current timestamp automatically when you are creating the image, and it will make the browser look again for the image instead of retrieving the one in the cache.
share
...
Git push existing repo to a new and different remote repo server?
Say I have a repository on git.fedorahosted.org and I want to clone this into my account at github to have my own playground aside from the more "official" repo on fedorahosted.
What would be the steps to initially copy that over?
Within github there is this nice "fork" button, but I can't use thi...
What is a “web service” in plain English?
...
This explanation is good, but what breaks ability to consume the random integer by other program from HTML? There are plenty of libraries to read HTML and this is the same as reading XML for me, and almost same as reading JSON. I know this post very old, though comment pleas...