String Multiple methods for intercepting strings

1. Intercept the string and return the string array:

  String str="123,abc,456,def";
  String[]  strs=str.split(",");
  for (int i=0;i<strs.length;i++){
    
    
     Log.e("TAG","打印第"+i+"个数据是---"+strs[i]);
  }      

• The printed results are as follows:

打印第0个数据是---123
打印第1个数据是---abc
打印第2个数据是---456
打印第3个数据是---def

Second, specify the index subscript:

• 2 start index 5 end index

 String str="0123456789";
 //指定索引 2开始索引 5结束索引
 String substring = str.substring(2, 5);
 Log.e("TAG","打印数据是---"+substring);

• The printed results are as follows:

打印数据是---234

3. Specify the index subscript:

• index 4 to end

 String str="0123456789";
 //指定索引 4到末尾
 String substring = str.substring(4);
 Log.e("TAG","打印数据是---"+substring);

• The printed results are as follows:

打印数据是---456789

4. Specify the index to the specified character "?":

• indexOf 0 starts to the first character "_"
• indexOf 0 starts to the last character "_"

 String str="123_abc_456";
 String substring = str.substring(0,str.indexOf("_"));
 String substring1 = str.substring(0,str.lastIndexOf("_"));
 String substring2 = str.substring(str.lastIndexOf("_")+1);
 Log.e("TAG","打印数据是---"+substring);
 Log.e("TAG","打印数据是---"+substring1);
 Log.e("TAG","打印数据是---"+substring2);

• The printed results are as follows:

打印数据是---123
打印数据是---123_abc
打印数据是---456

5. Intercept specified digits from the back:

 String message="123456789_00";
 String substring = message.substring(message.length()-5);
 Log.e("TAG","打印数据是---"+substring);

• The printed results are as follows:

打印数据是---89_00