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Is is possible to check if an object is already attached to a data context in Entity Framework?
...// Track whether we need to perform an attach
bool attach = false;
if (
context.ObjectStateManager.TryGetObjectStateEntry
(
context.CreateEntityKey(entitySetName, entity),
out entry
)
)
{
// Re-attach if nece...
Disable pasting text into HTML form
... var onload = window.onload;
window.onload = function () {
if (typeof onload == "function") {
onload.apply(this, arguments);
}
var fields = [];
var inputs = document.getElementsByTagName("input");
var textareas = document.getElementsByTagN...
How to check if an object is a list or tuple (but not string)?
...an be treated as a list. So, don't check for the type of a list, just see if it acts like a list.
But strings act like a list too, and often that is not what we want. There are times when it is even a problem! So, check explicitly for a string, but then use duck typing.
Here is a function I wro...
How to make sure that string is valid JSON using JSON.NET
...est way would be to Parse the string using JToken.Parse, and also to check if the string starts with { or [ and ends with } or ] respectively (added from this answer):
private static bool IsValidJson(string strInput)
{
if (string.IsNullOrWhiteSpace(strInput)) { return false;}
strInput = strI...
How can I use break or continue within for loop in Twig template?
...s a flag to break iterating:
{% set break = false %}
{% for post in posts if not break %}
<h2>{{ post.heading }}</h2>
{% if post.id == 10 %}
{% set break = true %}
{% endif %}
{% endfor %}
An uglier, but working example for continue:
{% set continue = false %}
{% ...
How to remove local (untracked) files from the current Git working tree
...rrent directory.
Normally, only files unknown to Git are removed, but if the -x option is specified, ignored files are also removed. This can, for example, be useful to remove all build products.
If any optional <path>... arguments are given, only those paths are affected.
Step 1...
Key existence check in HashMap
...
Do you ever store a null value? If not, you can just do:
Foo value = map.get(key);
if (value != null) {
...
} else {
// No such key
}
Otherwise, you could just check for existence if you get a null value returned:
Foo value = map.get(key);
if (v...
Rails 3 check if attribute changed
Need to check if a block of attributes has changed before update in Rails 3.
5 Answers
...
Using a bitmask in C#
....None;
Logical bitwise combinations can be tough to remember, so I make life easier on myself with a FlagsHelper class*:
// The casts to object in the below code are an unfortunate necessity due to
// C#'s restriction against a where T : Enum constraint. (There are ways around
// this, but they'r...
How do I detect if I am in release or debug mode?
... is a boolean value that will be true for a debug build, false otherwise:
if (BuildConfig.DEBUG) {
// do something for a debug build
}
There have been reports that this value is not 100% reliable from Eclipse-based builds, though I personally have not encountered a problem, so I cannot say how ...