如何在 Java (Android) 中使用 getMonth 添加前导零
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How to add Leading Zero with getMonth in Java (Android)
提问by Robby
I'm using an int variable:
我正在使用一个 int 变量：
month = dp.getMonth() + 1;
currently getting an output of "2" and when I do the following:
当前获得“2”的输出，当我执行以下操作时：
if (month<10){
month = '0'+month;
};
I get: 50.
我得到：50。
回答by Simon M?Kenzie
Your problem is that your '0'charis being coerced to an integer. Since '0'has an ASCII value of 48, you're getting 48 + 2 = 50.
您的问题是您'0'char被强制为整数。由于'0'ASCII 值为48，因此您将获得48 + 2 = 50.
Note that what you're trying to do won't work - you can't add a leading 0to month, as monthis a number. A leading zero only makes sense in a string representationof a number.
请注意，您尝试执行的操作是行不通的 - 您不能像数字一样将前导添加0到。前导零仅在数字的字符串表示中有意义。monthmonth
As explained in this answer, here's how to produce a zero-padded number:
如本答案所述，以下是生成零填充数字的方法：
String.format("%02d", month);
