conditional-operator

问题 This may be the way my server is set up, but I'm banging my head against the wall. I'm trying to say that if $action has no value or has a value that is not "add" or "delete" then have an error, else keep running the script. However, I get an error no matter what $action is. $action = $_GET['a']; if((!isset($action)) || ($action != "add" || $action != "delete")){ //header("location:index.php"); echo "error <br>"; } $action is being set properly and if run something like if($action =="add") it

问题 I want to check if the role is agency then the output is $agencyUsers else if the role is officer then the output is $officeUsers else I need to output 'No Group' I try this but the output is 'No Group' for all users <td>{{ strtolower($user->getRoleNames()) === 'agency' ? $agencyUsers : strtolower($user->getRoleNames()) === 'officer' ? $officeUsers : 'No Group'}}</td> 回答1: You must wrap the second ternary in parentheses, this should work: strtolower($user->getRoleNames()) === 'agency' ?

问题 As per C precedence tables, the ternary conditional operator has right-to-left associativity. So, is it directly convertible to the equivalent if-else ladder? For example, can: x?y?z:u:v; be interpreted as: if(x) { if(y) { z; } else { u; } } else { v; } by matching an else ( : ) with the closest unpaired if ( ? )? Or does right-to-left associativity imply some other arrangement? 回答1: The example you gave could only be interpreted in one way (like the if statements you gave), whether the

问题 I want to only include history and ajaxify if the browser is ie9 or greater, OR is not ie: <!--[if gte IE 9]> <script type="text/javascript" src="assets/js/plugins/history.js"></script> <script type="text/javascript" src="assets/js/plugins/ajaxify.js"></script> <![endif]--> How can I use the OR operator to say this: <!--[if gte IE 9 | !IE ]> ?? Thanks! 回答1: This worked: <!--[if gte IE 9 | !IE ]><!--> <script type="text/javascript" src="assets/js/plugins/history.js"></script> <script type=

问题 I want to only include history and ajaxify if the browser is ie9 or greater, OR is not ie: <!--[if gte IE 9]> <script type="text/javascript" src="assets/js/plugins/history.js"></script> <script type="text/javascript" src="assets/js/plugins/ajaxify.js"></script> <![endif]--> How can I use the OR operator to say this: <!--[if gte IE 9 | !IE ]> ?? Thanks! 回答1: This worked: <!--[if gte IE 9 | !IE ]><!--> <script type="text/javascript" src="assets/js/plugins/history.js"></script> <script type=

问题 This question already has answers here : Multiple string comparison with C# (7 answers) Closed last year . I have this piece of code: if (filter != RECENT && filter != TODAY && filter != WEEK && filter != MONTH && filter != ALLTIME) { filter = RECENT; } Note that filter is a string and it's compared against const string types. Is there any way to do this inline and have it be more readable? Doing it with the ternary operator doesn't make it much better since I still have to repeat filter !=

问题 This question already has answers here : PHP if not equal(!=) and or (||) issue. Why doesnt this work? (6 answers) Closed last year . Hope u people will be fine. I’m working on a following code in which i want to use multiple php if conditions with multiple not operators (example is below), but when i execute following php code, it always returns true (mean content in always parenthesis always executed) even no condition is true. I want to ask what is the problem in following code. Is there

问题 This question already has answers here : Closed 9 years ago . Possible Duplicate: Conditional operator cannot cast implicitly? When writing a statement using the conditional operator, if the either of the expressions are numeric values they are always interpreted as int type. This makes a cast necessary to assign a short variable using this operator. bool isTrue = true; int intVal = isTrue ? 1 : 2; short shortVal = isTrue ? 1 : 2; // Compile error: Cannot implicitly convert type 'int' to

问题 This question already has answers here : Closed 9 years ago . Possible Duplicate: Conditional operator cannot cast implicitly? When writing a statement using the conditional operator, if the either of the expressions are numeric values they are always interpreted as int type. This makes a cast necessary to assign a short variable using this operator. bool isTrue = true; int intVal = isTrue ? 1 : 2; short shortVal = isTrue ? 1 : 2; // Compile error: Cannot implicitly convert type 'int' to

问题 I have been looking without much luck for an implementation of Python that converts infix to prefix that ranges on a sufficient amount of arithmetic and logic operators and care about its properties on a good python implementation. More specifically I am interested on the operators that would appear on a conditional clause of a C program . (e.g. it would transform a > 0 && b > 1 in prefix. Since I am still newbie to Python I would appreciate if anyone could offer me the implementation or some