C# StreamReader类用于从流中读取字符串。它继承自TextReader类，它提供Read()和ReadLine()方法从流中读取数据。
C# StreamReader示例：读取一行
下面来看看一个StreamReader类的简单例子，它从文件中读取一行数据。
using System
using System.IO
public class StreamReaderExample
{
public static void Main(string[] args)
{
FileStream f = new FileStream("e:\\myoutput.txt", FileMode.OpenOrCreate)
StreamReader s = new StreamReader(f)
string line = s.ReadLine()
Console.WriteLine(line)
string line2 = s.ReadLine()
Console.WriteLine(line2)
s.Close()
f.Close()
}
}
假设e:\myoutput.txt文件的内容如下 -
This is line 1
This is line 2
This is line 3
This is line 4
执行上面示例代码，得到以下输出结果 -
This is line 1
This is line 2
C# StreamReader示例：读取所有行
下面代码演示如何使用 StreamReader 来读取文件：myoutput.txt中的所有行内容 -
using System
using System.IO
public class StreamReaderExample
{
public static void Main(string[] args)
{
FileStream f = new FileStream("e:\\myoutput.txt", FileMode.OpenOrCreate)
StreamReader s = new StreamReader(f)
string line = ""
while ((line = s.ReadLine()) != null)
{
Console.WriteLine(line)
}
s.Close()
f.Close()
}
}
执行上面示例代码，得到以下输出结果 -
This is line 1
This is line 2
This is line 3
This is line 4