Utility class for Base64 encoding and decoding operations. Base64 编码和解码操作的工具类。 
在文件 Base64.x 第 5 行定义.
◆ decodeString()
  
  | 
        
          | static  final byte [] decodeString | ( | String |  | ) |  |  | static | 
 
 
◆ encodeToString() [1/2]
  
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          | static  final String encodeToString | ( | byte | [], |  
          |  |  | bool |  |  
          |  | ) |  |  |  | static | 
 
 
◆ encodeToString() [2/2]
  
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          | static  final String encodeToString | ( | byte | [], |  
          |  |  | int | , |  
          |  |  | int | , |  
          |  |  | bool |  |  
          |  | ) |  |  |  | static | 
 
Encodes 将指定范围的字节数组编码为 Base64 字符串。