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Unable to cast object of type 'System.DBNull' to type 'System.String`
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A shorter form can be used:
return (accountNumber == DBNull.Value) ? string.Empty : accountNumber.ToString()
EDIT: Haven't paid attention to ExecuteScalar. It does really return null if the field is absent in the return result. So use instead:
return (accountNumber == null) ? string.Empty :...
XPath - Selecting elements that equal a value
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The XPath spec. defines the string value of an element as the concatenation (in document order) of all of its text-node descendents.
This explains the "strange results".
"Better" results can be obtained using the expressions below:
//*[text() = 'qwe...
Change the Target Framework for all my projects in a Visual Studio Solution
...es
Private Class ProjectGuids
Public Const vsWindowsCSharp As String = "{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}"
Public Const vsWindowsVBNET As String = "{F184B08F-C81C-45F6-A57F-5ABD9991F28F}"
Public Const vsWindowsVisualCPP As String = "{8BC9CEB8-8B4A-11D0-8D11-00A0C91B...
Java split() method strips empty strings at the end? [duplicate]
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You can specify to apply the pattern as often as possible with:
String[] de = data.split(";", -1);
See the Javadoc for the split method taking two arguments for details.
share
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improve...
PHP expresses two different strings to be the same [duplicate]
...se they are too small.
For == in php,
If you compare a number with a string or the comparison involves
numerical strings, then each string is converted to a number and the
comparison performed numerically.
http://php.net/manual/en/language.operators.comparison.php
Attention:
What about...
What is the difference between typeof and instanceof and when should one be used vs. the other?
...f ClassSecond; // false
Use typeof for simple built in types:
'example string' instanceof String; // false
typeof 'example string' == 'string'; // true
'example string' instanceof Object; // false
typeof 'example string' == 'object'; // false
true instanceof Boolean; // false
typeof true == 'b...
Creating an instance using the class name and calling constructor
...Class.forName(className);
Constructor<?> ctor = clazz.getConstructor(String.class);
Object object = ctor.newInstance(new Object[] { ctorArgument });
That will only work for a single string parameter of course, but you can modify it pretty easily.
Note that the class name has to be a fully-q...
How to get the nth occurrence in a string?
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const string = "XYZ 123 ABC 456 ABC 789 ABC";
function getPosition(string, subString, index) {
return string.split(subString, index).join(subString).length;
}
console.log(
getPosition(string, 'ABC', 2) // --> 16
)
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Case-Insensitive List Search
I have a list testList that contains a bunch of strings. I would like to add a new string into the testList only if it doesn't already exist in the list. Therefore, I need to do a case-insensitive search of the list and make it efficient. I can't use Contains because that doesn't take into acc...
LINQ query to return a Dictionary
...c.SomePropToSortOn)
.ToDictionary(mc => mc.KeyProp.ToString(),
mc => mc.ValueProp.ToString(),
StringComparer.OrdinalIgnoreCase);
s...