java - Java 中 "if statement"的问题

Question

看一下下面的java代码。

String Remark="";
boolean Paid, PartiallyPaid, NotPaid;
if(Paid=true) {Remark="Paid";}
if(PartiallyPaid=true) {Remark="Partially Paid";}
if(NotPaid=true)  {Remark="Not Paid";}

这里的 boolean 值由单选按钮确定。我想如上所述分配字符串“Remark”。但它总是只给出最后的分配值(作为“未支付”)。有人解释一下为什么会发生这种情况吗？

Answer 1

使用 == 而不是 = 进行比较。

== 用于比较两个值是否相等

= 用于将一个值分配给另一个值

String Remark="";
boolean Paid, PartiallyPaid, NotPaid;  // initialise values else compile error, pointed out by  Peter O.
if(Paid==true) {Remark="Paid";}
if(PartiallyPaid==true) {Remark="Partially Paid";}
if(NotPaid==true)  {Remark="Not Paid";}

正如unholysampler所指出的

对于 boolean 值，您不必显式检查是否相等。以下就可以了

String Remark="";
boolean Paid, PartiallyPaid, NotPaid;  // initialise values else compile error, pointed out by  Peter O.
if(Paid) {Remark="Paid";}
if(PartiallyPaid) {Remark="Partially Paid";}
if(NotPaid)  {Remark="Not Paid";}