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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
... should remember that it is not C# source that executes but rather IL:
IL_0001: ldnull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenc...
How to get the first column of a pandas DataFrame as a Series?
...
df.set_index('x').y
– herrfz
Jan 10 '14 at 23:44
...
How to Remove ReadOnly Attribute on File Using PowerShell?
...
Thanks! This worked for me: dir . -r *.cs | % { $_.fullname } | % { attrib -r $_ }
– Cameron Taggart
Dec 7 '12 at 23:22
1
...
Choosing between MEF and MAF (System.AddIn)
.... While this sounds great, it comes with a heavy price you have to pay in order to cross appdomains. You pay this price in speed and also in the flexibility of the types that you can send back and forth.
MEF is more like dependency injection with some additional benefits such as discoverability a...
How to make return key on iPhone make keyboard disappear?
...on ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// _theTextField is the name of the parameter designated in the .h file.
_theTextField.returnKeyType = UIReturnKeyDone;
[_theTextField setDelegate:self];
}
// This part is more dynamic as it closes the keyboard regard...
Why do people put code like “throw 1; ” and “for(;;);” in front of json responses? [du
...that would betray the values written in object literals:
Object.prototype.__defineSetter__('x', function(x) {
alert('Ha! I steal '+x);
});
Then when a <script> was pointed at some JSON that used that property name:
{"x": "hello"}
the value "hello" would be leaked.
The way that arra...
Vertical (rotated) label in Android
... if(Gravity.isVertical(gravity) && (gravity&Gravity.VERTICAL_GRAVITY_MASK) == Gravity.BOTTOM) {
setGravity((gravity&Gravity.HORIZONTAL_GRAVITY_MASK) | Gravity.TOP);
topDown = false;
}else
topDown = true;
}
@Override
protected void onMeasu...
How and/or why is merging in Git better than in SVN?
...
This is largely an issue by the repository design that Subversion has, in order to create a branch you need to create a new virtual directory in the repository which will house a copy of the trunk but it doesn't store any information regarding when and what things got merged back in. That will lead...
MongoDB drop every database
...
Save this to drop_all_dbs.js:
var databases = db.getMongo().getDBNames()
for(var i in databases){
db = db.getMongo().getDB( databases[i] );
if(db.getName() == "admin" || db.getName() == "local"){
print("skipping db " + db.get...
What is the maximum float in Python?
...
For float have a look at sys.float_info:
>>> import sys
>>> sys.float_info
sys.floatinfo(max=1.7976931348623157e+308, max_exp=1024, max_10_exp=308, min=2.2
250738585072014e-308, min_exp=-1021, min_10_exp=-307, dig=15, mant_dig=53, epsil
on=...