blocks|key|3988065|text|您可以更新您的for循环条件，使其仅读取列表的前两个元素。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3988066|就像这样|3988067|public+void+read(){
++++InputStream+inputStream+=+getResources().openRawResource(R.raw.kfzkennzeichen);

++++BufferedReader+reader+=+new+BufferedReader(new+InputStreamReader(inputStream));
++++try+{
++++++++String+csvLine;
++++++++while+((csvLine+=+reader.readLine())+!=+null)+{
++++++++++++String[]+row+=+csvLine.split(",");
++++++++++++if+(row.lenght+>=+2){
+++++++++++++++for(int+i=0;+i<2;i%2B%2B){
++++++++++++++++++Log.d("ROWS",+row[i]);
++++++++++++++}
++++++++++++}else{
++++++++++++++++Log.d("Invalid+Row");
++++++++++++}
+}|code-block|syntax|javascript|3988068|希望这能有所帮助。|3988069|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You can update you for loop condition to only read first two element of list you have.

Something like

<pre><code>public void read(){
 InputStream inputStream = getResources().openRawResource(R.raw.kfzkennzeichen);

 BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
 try {
 String csvLine;
 while ((csvLine = reader.readLine()) != null) {
 String[] row = csvLine.split(",");
 if (row.lenght &gt;= 2){
 for(int i=0; i&lt;2;i++){
 Log.d("ROWS", row[i]);
 }
 }else{
 Log.d("Invalid Row");
 }
 }
</code></pre>

Hope this helps.

blocks|key|3984422|text|跳过打印最后一行：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3984423|for(int+i=0;+i<row.length+-+1;+i%2B%2B){
++++Log.d("ROWS",+row[i]);
}|code-block|syntax|javascript|3984424|如果您确定每行包含的值恰好为3个，请执行此操作。理想情况下，这些东西应该是可配置的。通常，您不希望只记录这些内容，因此可以考虑将数据映射到某个License.class，并使用license.getLetter()、license.getCity()或其他方法|3984425|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Skip printing last line:

<pre><code>for(int i=0; i&lt;row.length - 1; i++){
 Log.d("ROWS", row[i]);
}
</code></pre>

Do it if you are sure each line contains exactly 3 values. Ideally this stuff should be configurable. In general you don't want just log the stuff so consider mapping data to some License.class and using license.getLetter(), license.getCity() or whatever

blocks|key|3984439|text|//ideally,+this+should+be+on+config+file
int+maxIndexToRead+=+2;

for(int+i=0;+i<+maxIndexToRead;i%2B%2B)
{
+++++Log.d("ROWS",+row[i]);
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|3984440|是的，Allman风格规则；)|unstyled|3984441|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>//ideally, this should be on config file
int maxIndexToRead = 2;

for(int i=0; i&lt; maxIndexToRead;i++)
{
 Log.d("ROWS", row[i]);
}
</code></pre>

And yes, Allman style rules ; )

blocks|key|3988207|text|如果你想这样，你可以去掉for循环：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3988208|public+void+read()+{
++++InputStream+inputStream+=+getResources().openRawResource(R.raw.carplates);

++++BufferedReader+reader+=+new+BufferedReader(new+InputStreamReader(inputStream));
++++try+{
++++++++String+csvLine;
++++++++while((csvLine+=+reader.readLine())+!=+null)+{
++++++++++++String[]+row+=+csvLine.split(",");
++++++++++++Log.d("First+capital+letter+of+the+city:+",+row[0]);
++++++++++++Log.d("City:+",+row[1]);
++++++++}
++++}+catch(...)+{
++++++++//...
++++}
}|code-block|syntax|javascript|3988209|但正如@Akceptor在另一个答案中指导的那样，只有当您确定CSV始终采用这种格式时，才能这样做。|3988210|同样，使用这种方法，如果您愿意，可以很容易地将行转换为类实例。|3988211|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|$]]

You can eliminate your for-loop if you want like:

<pre><code>public void read() {
 InputStream inputStream = getResources().openRawResource(R.raw.carplates);

 BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
 try {
 String csvLine;
 while((csvLine = reader.readLine()) != null) {
 String[] row = csvLine.split(",");
 Log.d("First capital letter of the city: ", row[0]);
 Log.d("City: ", row[1]);
 }
 } catch(...) {
 //...
 }
}
</code></pre>

But as @Akceptor mentinoed in another answer, do this only if you are sure that tha CSV is always in this format.

Also with this approach you cna easily convert your row to a class instance if you want.

I have a csv file that contains german car license plates. The structure is as follows:
B,Berlin, Germany
the first one B is the first capital letter of the city, the second position is the City, and the third position is the state 

I only want the first two positions, only B and Berlin

I know how to read a CSV File in Java, but I don't know how I can tell the compiler to "ignore" the third position?

<pre><code>public void read(){
 InputStream inputStream = getResources().openRawResource(R.raw.carplates);

 BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
 try {
 String csvLine;
 while ((csvLine = reader.readLine()) != null) {
 String[] row = csvLine.split(",");
 for(int i=0; i&lt;row.length;i++){
 Log.d("ROWS", row[i]);
 }
 }
</code></pre>

The output is an Array that contains B, Berlin and Germany. Since there are 400 plates, it is impossible to delete manually the state in the csv file.
What is the trick here? 

Thank you in advance

[CLEARING]

all the elements are in the same line: <code>B,Berlin,Germany,M,Munich,Germany...</code>

Get only the first two positions of CSV in Java

编译器

Java

我有一个包含德国车牌的csv文件。结构如下: B，柏林，德国第一个B是城市的第一个大写字母，第二个位置是城市，第三个位置是州我只想要前两个位置，B和柏林我知道如何在Java中读取CSV文件，但我不知道如何告诉编译器“忽略”第三个位置？public void read(){    InputStream inputStr...

问只获取Java中CSV的前两个位置
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