parameters

问题 I have a method call expression and try to invoke the method. I figured out a way, but I have problems in retrieving the parameter values since not every argument is described with a ConstantExpression. Expression<Action<T>> = t => t.DoSomething(Par0, Par1, Par2); MethodCallExpression methodCallExpression = selector.Body as MethodCallExpression; // get the information which is needed to invoke the method from the provided // lambda expression. MethodInfo methodInfo = methodCallExpression

问题 I recently read (and unfortunately forgot where), that the best way to write operator= is like this: foo &operator=(foo other) { swap(*this, other); return *this; } instead of this: foo &operator=(const foo &other) { foo copy(other); swap(*this, copy); return *this; } The idea is that if operator= is called with an rvalue, the first version can optimize away construction of a copy. So when called with a rvalue, the first version is faster and when called with an lvalue the two are equivalent.

问题 Just installed Ghostscript 8.54 for Windows. Does anyone know of the minimum parameters to pass to gswin32c.exe to make it convert, say, someFile.eps to someFile.eps.pdf ? 回答1: Since the question was about the "minimum parameters to pass to gswin32c.exe to make it convert, say, someFile.eps to someFile.eps.pdf" , let me give an answer: c:/path/to/gswin32c.exe ^ -sDEVICE=pdfwrite ^ -o c:/path/to/output.pdf ^ c:/path/to/input.eps or even shorter: gswin32c ^ -sDEVICE=pdfwrite ^ -o output.pdf ^

问题 Consider the following code: function Test { [CmdletBinding()] param ( [parameter(Mandatory=$true)] [AllowNull()] [String] $ComputerName ) process{} } Test -ComputerName $null Based on the official documentation for AllowNull I was expecting that $ComputerName could either be [string] or $null . However, running the above code results in the following error: [14,24: Test] Cannot bind argument to parameter 'ComputerName' because it is an empty string. Why doesn't passing $null for

问题 As this function can take unknown numbers of parameters: function BulkParam(){ return func_get_args(); } A print_r will print only the values, but how i can retrieve the variable names as well as the array key? For example: $d1 = "test data"; $d2 = "test data"; $d3 = "test data"; print_r(BulkParam($d1, $d2, $d3)); It will print this: Array ( [0] => test data [1] => test data [2] => test data ) But i want to have the variables name as the index name or key name of all arrays. Then the array

问题 Sometimes I encounter cases where I have to attach a method to a delegate but the signature doesn't match, like trying to attach abc down there to somedelegate with the string parameter being "hi". public class test { //... public void abc(int i, string x) { //Do Something } //... } public class test2 { somedelegate x; //... public test2() { //Do Something test y = new test(); x += y.abc(,"hi"); } delegate void somedelegate(int i); } I can work it around by creating another delegate with the

问题 I am uploading an image to an asmx web service. The file upload works fine, but I am wondering how to access the parameters that I set in the javascript for the filetransfer. I want to pass the image number to the asmx SaveImage web method. Then after the file has successfully been saved I want to return the image number to the Javascript. //Javascript Calling Web Service function uploadPhoto(imageURI, imageNumber) { var options = new FileUploadOptions(), params = {}, ft = new FileTransfer(),

问题 I'm using Eclipse IDE to develop an android app. I'm trying to connect to a .net webservice. I'm using ksoap2 version 2.3 When I'm calling a webmethod with no parameters, it works fine. When I come to pass a parameter to the webmethod, I get null (while debugging the webservice I discovered that) and I get a null from the webmethod in the client side code. Code: package com.examples.hello; import org.ksoap2.SoapEnvelope; import org.ksoap2.serialization.PropertyInfo; import org.ksoap2

问题 Is there a way to include a Twig-template with more than one parameter? I tried this, but it didn't work: The following Twig is rendered by my Symfony Controller: {% for object in objects %} {% if object.type == "simple" %} {% include 'BBLWebBundle:content:simple.html.twig' with [{'picture': object.picture}, {'link': object.link}, {'name': object.name}, {'info': object.info}] %} {% elseif object.type == "mp3" %} {% include 'BBLWebBundle:content:mp3.html.twig' with [{'picture': object.picture}

问题 I am trying to write results of some processing into SQL Server table. My results are store in a list of lists where each item of the list is a list. I am using parameters (6 params) and I am getting the following error: cnxn.execute(sqlStatement, (item[0],item[1],item[2],item[3],item[4],item[5])) pyodbc.ProgrammingError: ('The SQL contains 0 parameter markers, but 6 parameters were supplied', 'HY000') That's my code sqlStatement = "INSERT INTO CEA_CR (`SessionID`, `Session.Call_TYPE_Assigned