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如何将长转换/转换为字符串?

[英]How to convert / cast long to String?

I just created sample BB app, which can allow to choose the date.我刚刚创建了示例 BB 应用程序,它可以允许选择日期。

DateField curDateFld = new DateField("Choose Date: ",
  System.currentTimeMillis(), DateField.DATE | DateField.FIELD_LEFT);

After choosing the date, I need to convert that long value to String, so that I can easily store the date value somewhere in database.选择日期后,我需要将该长值转换为字符串,以便我可以轻松地将日期值存储在数据库中的某处。 I am new to Java and Blackberry development.我是 Java 和 Blackberry 开发的新手。

long date = curDateFld.getDate();

How should I convert this long value to String?我应该如何将这个长值转换为字符串? Also I want to convert back to long from String.另外我想从String转换回long。 I think for that I can use long l = Long.parseLong("myStr");我认为为此我可以使用long l = Long.parseLong("myStr"); ? ?

See the reference documentation for the String class : String s = String.valueOf(date);请参阅String 类参考文档String s = String.valueOf(date);

If your Long might be null and you don't want to get a 4-letter "null" string, you might use Objects.toString , like: String s = Objects.toString(date, null);如果您的 Long 可能为空并且您不想获得 4 个字母的"null"字符串,您可以使用Objects.toString ,例如: String s = Objects.toString(date, null);


EDIT:编辑:

You reverse it using Long l = Long.valueOf(s);您可以使用Long l = Long.valueOf(s);反转它Long l = Long.valueOf(s); but in this direction you need to catch NumberFormatException但在这个方向上你需要抓住NumberFormatException

String strLong = Long.toString(longNumber);

简单且工作正常:-)

Long.toString()

The following should work:以下应该工作:

long myLong = 1234567890123L;
String myString = Long.toString(myLong);

very simple, just concatenate the long to a string.非常简单,只需将 long 连接到一个字符串。

long date = curDateFld.getDate(); 
String str = ""+date;

1. 1.

long date = curDateFld.getDate();
//convert long to string
String str = String.valueOf(date);

//convert string to long
date = Long.valueOf(str);

2. 2.

 //convert long to string just concat long with empty string
 String str = ""+date;
//convert string to long

date = Long.valueOf(str);
String logStringVal= date+"";

Can convert the long into string object, cool shortcut for converting into string...but use of String.valueOf(date);可以将 long 转换为字符串对象,很酷的转换为字符串的快捷方式...但是使用String.valueOf(date); is advisable是可取的

只需这样做:

String strLong = Long.toString(longNumber);
String longString = new String(""+long);

要么

String longString = new Long(datelong).toString();

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