只读指定范围

Question

我有一个文本文件，我只想从中读取指定的跨度（如位置20到80）。

我正在使用下面的代码，但它从0读取跨度的长度。

char[] buffer = new char[span.Length]; 
using (StreamReader reader = new StreamReader(filename)) 
{    
    reader.ReadBlock(buffer, 0, span.Length); 
} 

有人可以帮我吗？由于

Answer 1

char[] buffer = new char[span.Length]; 
using (StreamReader reader = new StreamReader(filename)) 
{  
    reader.BaseStream.Seek(span.Start, SeekOrigin.Begin); // or SeekOrigin.Current if you want to loop 
    reader.Read(buffer, 0, span.Length); 
} 

假设的span类型有Start属性。

Answer 2

你试过了吗？

char[] buffer = new char[span.Length]; 
using (StreamReader reader = new StreamReader(filename)) 
{    
    reader.ReadBlock(buffer, 20, span.Length); 
} 

Answer 3

char[] buffer = new char[span.Length]; 
using (StreamReader reader = new StreamReader(filename)) 
{    
    reader.ReadBlock(buffer, startIndex, span.Length); 
} 

的startIndex =从哪里开始
span.Length =字符的数量阅读