blocks|key|390848|text|应该使用\而不是/进行转义。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|390849|这样r.append('\n');或r.append("\n");就可以工作了(StringBuilder重载了char和String类型的方法)。|390850|entityMap^0|4|1|8|1|0|2|F|I|F|14|D|1K|4|1P|6|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|I|$]]

Escape should be done with <code>\</code>, not <code>/</code>.

So <code>r.append('\n');</code> or <code>r.append("\n");</code> will work (<code>StringBuilder</code> has overloaded methods for <code>char</code> and <code>String</code> type).

blocks|key|390872|text|它应该是|type|unstyled|depth|inlineStyleRanges|entityRanges|data|390873|r.append("\n");|code-block|syntax|javascript|390874|但我建议你这样做，|390875|r.append(System.getProperty("line.separator"));|390876|System.getProperty("line.separator")在java中提供了依赖于系统的换行符。在Java7中还有一个直接返回值的方法：System.lineSeparator()|offset|length|style|CODE|390877|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/7/docs/api/java/lang/System.html#lineSeparator%2528%2529^0|0|0|0|0|0|10|23|M|23|M|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|12|8|@$M|13|N|14|O|P]|$M|15|N|16|O|P]]|9|@$M|17|N|18|1|19]]|A|$]]|$1|Q|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]]]

It should be 

<pre><code>r.append("\n");
</code></pre>

But I recommend you to do as below,

<pre><code>r.append(System.getProperty("line.separator"));
</code></pre>

<code>System.getProperty("line.separator")</code> gives you system-dependent newline in java. Also from Java 7 there's a method that returns the value directly: <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/System.html#lineSeparator%28%29" rel="noreferrer"><code>System.lineSeparator()</code></a>

blocks|key|390920|text|另一种选择是使用Apache+Commons+StrBuilder，它具有StringBuilder中缺少的功能。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|390921|StrBuilder.appendLn()|offset|length|390922|从3.6版开始，StrBuilder已被弃用，取而代之的是具有相同功能的TextStringBuilder|390923|entityMap|0|LINK|mutability|MUTABLE|url|https://commons.apache.org/proper/commons-lang/javadocs/api-3.1/org/apache/commons/lang3/text/StrBuilder.html#appendln(org.apache.commons.lang3.text.StrBuilder)|1|https://commons.apache.org/proper/commons-text/apidocs/org/apache/commons/text/TextStringBuilder.html^0|0|0|L|0|0|10|H|1|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@$D|T|E|U|1|V]]|A|$]]|$1|F|3|G|5|6|7|W|8|@]|9|@$D|X|E|Y|1|Z]]|A|$]]|$1|H|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]|P|$5|K|L|M|A|$N|Q]]]]

Another option is to use Apache Commons StrBuilder, which has the functionality that's lacking in StringBuilder.

<a href="https://commons.apache.org/proper/commons-lang/javadocs/api-3.1/org/apache/commons/lang3/text/StrBuilder.html#appendln(org.apache.commons.lang3.text.StrBuilder)" rel="noreferrer">StrBuilder.appendLn()</a>

As of version 3.6 StrBuilder has been deprecated in favour of <a href="https://commons.apache.org/proper/commons-text/apidocs/org/apache/commons/text/TextStringBuilder.html" rel="noreferrer">TextStringBuilder</a> which has the same functionality

blocks|key|172975|text|您可以使用line.seperator将新行追加到|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|172976|entityMap^0|5|E|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

you can use <code>line.seperator</code> for appending new line in

blocks|key|390981|text|您还可以在String.format+(参见java.util.Formatter)中使用行分隔符，它也是平台无关的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|390982|即：|390983|result.append(String.format("%25n",+""));|code-block|syntax|javascript|390984|如果需要添加更多的行距，只需使用：|390985|result.append(String.format("%25n%25n",+""));|390986|您还可以使用StringFormat格式化整个字符串，在字符串的末尾加上一个换行符。|390987|result.append(String.format("%2510s%25n%25n",+"This+is+my+string."));|390988|entityMap^0|5|D|M|J|0|0|0|0|0|6|C|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|13|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|15|8|@$9|16|A|17|B|C]]|D|@]|E|$]]|$1|S|3|T|5|J|7|18|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|V|$]]

You can also use the line separator character in <code>String.format</code> (See <code>java.util.Formatter</code>), which is also platform agnostic. 

i.e.:

<pre><code>result.append(String.format("%n", ""));
</code></pre>

If you need to add more line spaces, just use:

<pre><code>result.append(String.format("%n%n", ""));
</code></pre>

You can also use <code>StringFormat</code> to format your entire string, with a newline(s) at the end.

<pre><code>result.append(String.format("%10s%n%n", "This is my string."));
</code></pre>

blocks|key|173041|text|我创建了类似于StringBuidler的原始类，可以通过调用方法appendLine(String+str)来追加行。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|173042|public+class+StringBuilderPlus+{

++++private+StringBuilder+sb;

++++public+StringBuilderPlus(){
+++++++++sb+=+new+StringBuilder();
++++}

++++public+void+append(String+str)
++++{
++++++++sb.append(str+!=+null+?+str+:+"");
++++}

++++public+void+appendLine(String+str)
++++{
++++++++sb.append(str+!=+null+?+str+:+"").append(System.getProperty("line.separator"));
++++}

++++public+String+toString()
++++{
++++++++return+sb.toString();
++++}
}|code-block|syntax|javascript|173043|用法：|173044|StringBuilderPlus+sb+=+new+StringBuilderPlus();
sb.appendLine("aaaaa");
sb.appendLine("bbbbb");
System.out.println(sb.toString());|173045|控制台：|173046|aaaaa
bbbbb|173047|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

I create original class that similar to StringBuidler and can append line by calling method appendLine(String str).

<pre><code>public class StringBuilderPlus {

 private StringBuilder sb;

 public StringBuilderPlus(){
 sb = new StringBuilder();
 }

 public void append(String str)
 {
 sb.append(str != null ? str : "");
 }

 public void appendLine(String str)
 {
 sb.append(str != null ? str : "").append(System.getProperty("line.separator"));
 }

 public String toString()
 {
 return sb.toString();
 }
}
</code></pre>

Usage:

<pre><code>StringBuilderPlus sb = new StringBuilderPlus();
sb.appendLine("aaaaa");
sb.appendLine("bbbbb");
System.out.println(sb.toString());
</code></pre>

Console:

<pre><code>aaaaa
bbbbb
</code></pre>

blocks|key|173103|text|对于Kotlin来说|type|unstyled|depth|inlineStyleRanges|entityRanges|data|173104|StringBuilder().appendLine("your+text");|offset|length|style|CODE|173105|虽然这是一个java问题，但这也是google对Kotlin的第一个结果，可能会派上用场。|173106|entityMap^0|0|0|14|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@$D|N|E|O|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|K|$]]

For Kotlin,
<code>StringBuilder().appendLine(&quot;your text&quot;);</code>
Though this is a java question, this is also the first google result for Kotlin, might come in handy.

blocks|key|173187|text|除了K.S创建StringBuilderPlus类并利用适配器模式扩展最终类的响应之外，如果您利用泛型并在新的append和appendLine方法中返回StringBuilderPlus对象，则可以对所有不同的类型使用StringBuilders的许多append方法，同时重新获得将多个append命令串接到一起的能力，如下所示|type|unstyled|depth|inlineStyleRanges|entityRanges|data|173188|public+class+StringBuilderPlus+{

++++private+final+StringBuilder+stringBuilder;

++++public+StringBuilderPlus()+{
++++++++this.stringBuilder+=+new+StringBuilder();
++++}

++++public+<T>+StringBuilderPlus+append(T+t)+{
++++++++stringBuilder.append(t);
++++++++return+this;
++++}

++++public+<T>+StringBuilderPlus+appendLine(T+t)+{
++++++++stringBuilder.append(t).append(System.lineSeparator());
++++++++return+this;
++++}

++++@Override
++++public+String+toString()+{
++++++++return+stringBuilder.toString();
++++}

++++public+StringBuilder+getStringBuilder()+{
++++++++return+stringBuilder;
++++}
}|code-block|syntax|javascript|173189|然后，您可以像使用原始的StringBuilder类一样使用它：|173190|StringBuilderPlus+stringBuilder+=+new+StringBuilderPlus();
stringBuilder.appendLine("test")
++++.appendLine('c')
++++.appendLine(1)
++++.appendLine(1.2)
++++.appendLine(1L);

stringBuilder.toString();|173191|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]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

In addition to K.S's response of creating a StringBuilderPlus class and utilising ther adapter pattern to extend a final class, if you make use of generics and return the StringBuilderPlus object in the new append and appendLine methods, you can make use of the StringBuilders many append methods for all different types, while regaining the ability to string string multiple append commands together, as shown below

<pre><code>public class StringBuilderPlus {

 private final StringBuilder stringBuilder;

 public StringBuilderPlus() {
 this.stringBuilder = new StringBuilder();
 }

 public &lt;T&gt; StringBuilderPlus append(T t) {
 stringBuilder.append(t);
 return this;
 }

 public &lt;T&gt; StringBuilderPlus appendLine(T t) {
 stringBuilder.append(t).append(System.lineSeparator());
 return this;
 }

 @Override
 public String toString() {
 return stringBuilder.toString();
 }

 public StringBuilder getStringBuilder() {
 return stringBuilder;
 }
}
</code></pre>

you can then use this exactly like the original StringBuilder class:

<pre><code>StringBuilderPlus stringBuilder = new StringBuilderPlus();
stringBuilder.appendLine("test")
 .appendLine('c')
 .appendLine(1)
 .appendLine(1.2)
 .appendLine(1L);

stringBuilder.toString();
</code></pre>

I have a <a href="http://docs.oracle.com/javase/8/docs/api/java/lang/StringBuilder.html"><code>StringBuilder</code></a> object,

<pre><code>StringBuilder result = new StringBuilder();
result.append(someChar);
</code></pre>

Now I want to append a newline character to the <code>StringBuilder</code>. How can I do it?

<pre><code>result.append("/n"); 
</code></pre>

Does not work. So, I was thinking about writing a newline using Unicode. Will this help? If so, how can I add one?

How to append a newline to StringBuilder

Kotlin

我有一个对象，StringBuilder result = new StringBuilder();result.append(someChar);现在，我想在StringBuilder后面添加一个换行符。我该怎么做呢？result.append("/n"); 不起作用。所以，我在考虑用Unicode写一个换行符。这会...

问如何在StringBuilder中添加换行符
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