如何检测变量是否已更改?

本文介绍了如何检测变量是否已更改?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我发现自己仅在变量已更改的情况下才想在程序中执行某些操作.到目前为止，我一直在做这样的事情:

I have found myself wanting to do certain things in my programs only if a variable has changed. I have so far been doing something like this:

int x = 1; int initialx = x; ...//code that may or may not change the value of x if (x!=initialx){ doOneTimeTaskIfVariableHasChanged(); initialx = x; //reset initialx for future change tests }

是否有更好/更简单的方法?

Is there a better/simpler way of doing this?

推荐答案

由于您只想在值更改时才查找并执行某些操作，因此我将使用setXXX，例如:

Since you want to find and perform some action only if the value changes, I would go with setXXX, for example:

public class X { private int x = 1; //some other code here public void setX(int proposedValueForX) { if(proposedValueForX != x) { doOneTimeTaskIfVariableHasChanged(); x = proposedValueForX; } } }