blocks|key|1607859|text|对于任何感兴趣的人来说，这只是Frasers函数的一个小小的变化。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1607860|function+setPrecision(number:Number,+precision:int)+{
+precision+=+Math.pow(10,+precision);
+return+(Math.round(number+*+precision)/precision);
}|code-block|syntax|javascript|1607861|因此，使用：|1607862|var+number:Number+=+10.98813311;
trace(setPrecision(number,1));+//Result+is+10.9
trace(setPrecision(number,2));+//Result+is+10.98
trace(setPrecision(number,3));+//Result+is+10.988+and+so+on|1607863|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/632914/3709765^0|F|7|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

Just a slight variation on <a href="https://stackoverflow.com/a/632914/3709765">Frasers</a> Function, for anyone who is interested.

<pre><code>function setPrecision(number:Number, precision:int) {
 precision = Math.pow(10, precision);
 return (Math.round(number * precision)/precision);
}
</code></pre>

So to use:

<pre><code>var number:Number = 10.98813311;
trace(setPrecision(number,1)); //Result is 10.9
trace(setPrecision(number,2)); //Result is 10.98
trace(setPrecision(number,3)); //Result is 10.988 and so on
</code></pre>

blocks|key|1607787|text|我在ActionScript+3中使用了Number.toFixed(precision)来做这件事：http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%2528%2529|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1607788|它正确地处理四舍五入，并指定要显示的小数点后的位数-不像Number.toPrecision()限制显示的总位数，而不考虑小数的位置。|1607789|var+roundDown:Number+=+1.434;+++++++++++++++++++++++++++++++++++++++++++++
//+will+print+1.43++++++++++++++++++++++++++++++++++++++++++++++++++++++++
trace(roundDown.toFixed(2));++++++++++++++++++++++++++++++++++++++++++++++

var+roundUp:Number+=+1.436;+++++++++++++++++++++++++++++++++++++++++++++++
//+will+print+1.44++++++++++++++++++++++++++++++++++++++++++++++++++++++++
trace(roundUp.toFixed(2));++++++++++++++++++++++++++++++++++++++++++++++++|code-block|syntax|javascript|1607790|entityMap|0|LINK|mutability|MUTABLE|url|http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%2528%2529^0|K|P|1F|1U|0|0|S|K|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|F|3|G|5|6|7|10|8|@$9|11|A|12|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|13|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|14|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

i've used <code>Number.toFixed(precision)</code> in ActionScript 3 to do this: <a href="http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%28%29" rel="noreferrer">http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%28%29</a>

it handles rounding properly and specifies the number of digits after the decimal to display - unlike <code>Number.toPrecision()</code> that limits the total number of digits to display regardless of the position of the decimal.

<pre><code>var roundDown:Number = 1.434; 
// will print 1.43 
trace(roundDown.toFixed(2)); 

var roundUp:Number = 1.436; 
// will print 1.44 
trace(roundUp.toFixed(2)); 
</code></pre>

blocks|key|1392954|text|我把BigDecimal的Java转换成了ActionScript。我们没有选择，因为我们计算财务应用程序。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1392955|http://code.google.com/p/bigdecimal/|offset|length|1392956|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|10|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@$D|O|E|P|1|Q]]|A|$]]|$1|F|3|-4|5|6|7|R|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|C]]]]

I converted the Java of BigDecimal to ActionScript.
We had no choices since we compute for financial application.

<a href="http://code.google.com/p/bigdecimal/" rel="nofollow noreferrer">http://code.google.com/p/bigdecimal/</a>

blocks|key|1392836|text|你可以使用property:舍入=“最近的”|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1392837|在NumberFormatter中，舍入有4个值可供选择:+rounding="none%7Cup%7Cdown%7Cnearest“。我认为根据您的情况，您可以选择取整=“最近”。|1392838|--+chary+--|1392839|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

You can use property: rounding = "nearest"

In NumberFormatter, rounding have 4 values which you can choice: rounding="none|up|down|nearest". I think with your situation, you can chose rounding = "nearest".

-- chary --

blocks|key|1393052|text|我发现BlazeDS还支持将Java对象序列化为ActionScript字符串。因此，如果你不需要ActionScript数据是数字(你不需要在Flex+/+ActionScript端做任何数学运算)，那么字符串映射工作得很好(不需要四舍五入)。有关BlazeDS映射选项，请参阅以下链接：http://livedocs.adobe.com/blazeds/1/blazeds_devguide/help.html?content=serialize_data_2.html|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1393053|entityMap|0|LINK|mutability|MUTABLE|url|http://livedocs.adobe.com/blazeds/1/blazeds_devguide/help.html?content=serialize_data_2.html^0|41|2K|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

I discovered that BlazeDS supports serializing Java BigDecimal objects to ActionScript Strings as well. So if you don't need the ActionScript data to be Numbers (you are not doing any math on the Flex / ActionScript side) then the String mapping works well (no rounding weirdness). See this link for the BlazeDS mapping options: <a href="http://livedocs.adobe.com/blazeds/1/blazeds_devguide/help.html?content=serialize_data_2.html" rel="nofollow noreferrer">http://livedocs.adobe.com/blazeds/1/blazeds_devguide/help.html?content=serialize_data_2.html</a>

blocks|key|1393209|text|Java2.2在GraniteDS中有BigDecimal，BigInteger和Long实现，这些类型的序列化选项，甚至代码生成工具选项，以便为相应的GraniteDS生成AS3大数字变量。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1393210|更多信息请点击这里：http://www.graniteds.org/confluence/display/DOC22/2.%2BBig%2BNumber%2BImplementations。|offset|length|1393211|entityMap|0|LINK|mutability|MUTABLE|url|http://www.graniteds.org/confluence/display/DOC22/2.%2BBig%2BNumber%2BImplementations^0|0|A|27|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

GraniteDS 2.2 has BigDecimal, BigInteger and Long implementations in ActionScript3, serialization options between Java / Flex for these types, and even code generation tools options in order to generate AS3 big numbers variables for the corresponding Java ones.

See more here: <a href="http://www.graniteds.org/confluence/display/DOC22/2.+Big+Number+Implementations" rel="nofollow noreferrer">http://www.graniteds.org/confluence/display/DOC22/2.+Big+Number+Implementations</a>.

blocks|key|1608263|text|我们能够在web上重用可用的BigDecimal.as类，并通过从AMF3Output派生来扩展class，您将需要在flex+xml文件中指定自己的端点类，在该自定义端点中，您可以插入自己的序列化程序来实例化AMF3Output子类。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1608264|public+class+EnhancedAMF3Output+extends+Amf3Output+{

++++public+EnhancedAMF3Output(final+SerializationContext+context)+{
++++++++super(context);
++++}

++++public+void+writeObject(final+Object+o)+throws+IOException+{+++++++++++
++++++++if+(o+instanceof+BigDecimal)+{
++++++++++++write(kObjectType);
++++++++++++writeUInt29(7);+//+write+U290-traits-ext+(first+3+bits+set)
++++++++++++writeStringWithoutType("java.math.BigDecimal");
++++++++++++writeAMFString(((BigDecimal)o).toString());
++++++++}+else+{
++++++++++++super.writeObject(o);
++++++++}
++++}
}|code-block|syntax|javascript|1608265|就这么简单！然后你就有了使用blazeds的原生BigDecimal支持，哇哦！确保您的BigDecimal+as3类实现了IExternalizable|1608266|干杯，jb|1608267|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

We were able to reuse one of the available BigDecimal.as classes on the web and extended blazeds by sublassing from AMF3Output, you'll need to specify your own endpoint class in the flex xml files, in that custom endpoint you can insert your own serializer that instantiates an AMF3Output subclass.

<pre><code>public class EnhancedAMF3Output extends Amf3Output {

 public EnhancedAMF3Output(final SerializationContext context) {
 super(context);
 }

 public void writeObject(final Object o) throws IOException { 
 if (o instanceof BigDecimal) {
 write(kObjectType);
 writeUInt29(7); // write U290-traits-ext (first 3 bits set)
 writeStringWithoutType("java.math.BigDecimal");
 writeAMFString(((BigDecimal)o).toString());
 } else {
 super.writeObject(o);
 }
 }
}
</code></pre>

as simple as that! then you have native BigDecimal support using blazeds, wooohoo!
Make sure your BigDecimal as3 class implements IExternalizable

cheers, jb

blocks|key|1393411|text|令人惊讶的是，MS+Excel中的round函数给出的值与您上面给出的值不同。例如在Excel中|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1393412|Round(143,355;2)+=+143,36|offset|length|style|CODE|1393413|因此，我对Excel舍入的解决方法如下：|1393414|public+function+setPrecision(number:Number,+precision:int):Number+{
precision+=+Math.pow(10,+precision);

const+excelFactor+:+Number+=+0.00000001;

number+%2B=+excelFactor;

return+(Math.round(number+*+precision)/precision);
}|code-block|syntax|javascript|1393415|entityMap^0|0|0|G|J|6|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@$D|S|E|T|F|G]|$D|U|E|V|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|W|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|X|8|@]|9|@]|A|$M|N]]|$1|O|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|P|$]]

Surprisingly the round function in MS Excel gives us different values then you have presented above.
For example in Excel

<code>Round(143,355;2)</code> = <code>143,36</code>

So my workaround for Excel round is like:

<pre><code>public function setPrecision(number:Number, precision:int):Number {
precision = Math.pow(10, precision);

const excelFactor : Number = 0.00000001;

number += excelFactor;

return (Math.round(number * precision)/precision);
}
</code></pre>

blocks|key|1608026|text|您可以在https://bugs.adobe.com/jira/browse/FP-3315的Flash+PLayer+Jira错误跟踪系统中投票并查看增强请求|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1608027|同时使用Number.toFixed()解决方法参见：(http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%2528%2529)|1608028|或者使用现有的开源实现：(http://code.google.com/p/bigdecimal/)或(http://www.fxcomps.com/money.html)|1608029|至于序列化工作，如果您使用Blazed或LCDS，那么序列化的工作量将会很小，因为它们确实支持(to+BigDecimal+)+cf。(http://livedocs.adobe.com/livecycle/es/sdkHelp/programmer/lcds/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&file=serialize_data_3.html)|1608030|entityMap|0|LINK|mutability|MUTABLE|url|https://bugs.adobe.com/jira/browse/FP-3315|1|http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%2528%2529|2|http://code.google.com/p/bigdecimal/|3|http://www.fxcomps.com/money.html|4|http://livedocs.adobe.com/livecycle/es/sdkHelp/programmer/lcds/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&file=serialize_data_3.html^0|4|16|0|0|S|1U|1|0|D|10|2|1G|X|3|0|1W|46|4|0^^$0|@$1|2|3|4|5|6|7|Z|8|@]|9|@$A|10|B|11|1|12]]|C|$]]|$1|D|3|E|5|6|7|13|8|@]|9|@$A|14|B|15|1|16]]|C|$]]|$1|F|3|G|5|6|7|17|8|@]|9|@$A|18|B|19|1|1A]|$A|1B|B|1C|1|1D]]|C|$]]|$1|H|3|I|5|6|7|1E|8|@]|9|@$A|1F|B|1G|1|1H]]|C|$]]|$1|J|3|-4|5|6|7|1I|8|@]|9|@]|C|$]]]|K|$L|$5|M|N|O|C|$P|Q]]|R|$5|M|N|O|C|$P|S]]|T|$5|M|N|O|C|$P|U]]|V|$5|M|N|O|C|$P|W]]|X|$5|M|N|O|C|$P|Y]]]]

You may vote and watch the enhancement request in the Flash PLayer Jira bug tracking system at <a href="https://bugs.adobe.com/jira/browse/FP-3315" rel="nofollow noreferrer">https://bugs.adobe.com/jira/browse/FP-3315</a>

And meanwhile use the Number.toFixed() work-around see :
(<a href="http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%28%29" rel="nofollow noreferrer">http://livedocs.adobe.com/flex/3/langref/Number.html#toFixed%28%29</a>)

or use the open source implementations out there : (<a href="http://code.google.com/p/bigdecimal/" rel="nofollow noreferrer">http://code.google.com/p/bigdecimal/</a>) or (<a href="http://www.fxcomps.com/money.html" rel="nofollow noreferrer">http://www.fxcomps.com/money.html</a>) 

As for the serialization efforts, well, it will be small if you use Blazeds or LCDS as they do support Java BigDecimal serialization (to String) cf. (<a href="http://livedocs.adobe.com/livecycle/es/sdkHelp/programmer/lcds/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&amp;file=serialize_data_3.html" rel="nofollow noreferrer">http://livedocs.adobe.com/livecycle/es/sdkHelp/programmer/lcds/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&amp;file=serialize_data_3.html</a>)

blocks|key|1392789|text|这看起来更像是一个交通问题，数字是正确的，但规模被忽略了。如果数字必须作为BigDecimal存储在服务器上，那么在发送它之前，您可能希望将其转换为服务器端不那么模糊的格式(数字、双精度、浮点数)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1392790|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

It seems more like a transport problem, the number being correct but the scale ignored. If the number has to be stored as a BigDecimal on the server you may want to convert it server side to a less ambiguous format (Number, Double, Float) before sending it.

I have BigDecimal objects serialized with BlazeDS to Actionscript. Once they hit Actionscript as Number objects, they have values like:

<code>140475.32</code> turns into <code>140475.31999999999998</code>

How do I deal with this? The problem is that if I use a <a href="http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/globalization/NumberFormatter.html" rel="nofollow noreferrer">NumberFormatter</a> with precision of 2, then the value is truncated to <code>140475.31</code>. Any ideas?

How to deal with Number precision in Actionscript?

代码生成工具

服务器

Java

我使用BlazeDS将BigDecimal对象序列化为Actionscript.当它们作为Number对象访问Actionscript时，它们的值如下所示：140475.32变成了140475.31999999999998我该如何处理这件事？问题是，如果我使用精度为2的，则该值将被截断为140475.31。有什么想法吗？

问如何在Actionscript中处理数字精度？
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问如何在Actionscript中处理数字精度？EN

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问如何在Actionscript中处理数字精度？
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