大约有 30,000 项符合查询结果（耗时：0.0396秒） [XML]
How to run `rails generate scaffold` when the model already exists?
...o generate a scaffold script.
it outputs:
rails g scaffold users fname:string lname:string bdate:date email:string encrypted_password:string
from your schema.rb our your renamed schema.rb. Check it
share
|
...
Is there a standard function to check for null, undefined, or blank variables in JavaScript?
... ) {
}
will evaluate to true if value is not:
null
undefined
NaN
empty string ("")
0
false
The above list represents all possible falsy values in ECMA-/Javascript. Find it in the specification at the ToBoolean section.
Furthermore, if you do not know whether a variable exists (that means, if ...
Deserialize json object into dynamic object using Json.net
...n.NET allows us to do this:
dynamic d = JObject.Parse("{number:1000, str:'string', array: [1,2,3,4,5,6]}");
Console.WriteLine(d.number);
Console.WriteLine(d.str);
Console.WriteLine(d.array.Count);
Output:
1000
string
6
Documentation here: LINQ to JSON with Json.NET
See also JObject.Parse ...
How do I copy an object in Java?
...
Create a copy constructor:
class DummyBean {
private String dummy;
public DummyBean(DummyBean another) {
this.dummy = another.dummy; // you can access
}
}
Every object has also a clone method which can be used to copy the object, but don't use it. It's way too easy...
How to get the integer value of day of week
How do I get the day of a week in integer format? I know ToString will return only a string.
9 Answers
...
Get the _id of inserted document in Mongo database in NodeJS
...ction.insert that will return the doc or docs inserted, which should have _ids.
Try:
collection.insert(objectToInsert, function(err,docsInserted){
console.log(docsInserted);
});
and check the console to see what I mean.
...
Regular vs Context Free Grammars
...re's an analogous pumping lemma for context-free languages that breaks the strings in the language into five parts, uvxyz, and where all instances of the language are in uvixyiz, for i ≥ 0. Now, you have two "nonterminals" that can be replicated, or pumped, as long as you have the same number.
...
Can I use CASE statement in a JOIN condition?
...T *
FROM sys.indexes i
JOIN sys.partitions p
ON i.index_id = p.index_id
JOIN sys.allocation_units a
ON CASE
WHEN a.type IN (1, 3) AND a.container_id = p.hobt_id THEN 1
WHEN a.type IN (2) AND a.container_id = p.partition_id THEN 1
EL...
How can I initialize an ArrayList with all zeroes in Java?
...os where nCopies is useful with reference types: Immutable objects such as strings, null-object patterns, enum constants, ... Anyway, I updated the answer with a solution for creating 60 different objects.
– aioobe
Mar 2 '15 at 18:04
...
Is there any advantage of using map over unordered_map in case of trivial keys?
...(1) vs. O(log n) ). Most times I use a map, I use either int or std::string as the key type; hence, I've got no problems with the definition of the hash function. The more I thought about it, the more I came to realize that I can't find any reason of using a std::map over a std::unordered_...