blocks|key|1462251|text|包装：System.IO.FileSystem|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1462252|System.IO.File.ReadAllText("MyTextFile.txt");+?|code-block|syntax|javascript|1462253|entityMap|0|LINK|mutability|MUTABLE|url|https://www.nuget.org/packages/System.IO.FileSystem/^0|3|K|3|K|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Package: <a href="https://www.nuget.org/packages/System.IO.FileSystem/" rel="noreferrer"><code>System.IO.FileSystem</code></a>

<pre><code>System.IO.File.ReadAllText("MyTextFile.txt"); ?
</code></pre>

blocks|key|1660251|text|FileStream+fileStream+=+new+FileStream("file.txt",+FileMode.Open);
using+(StreamReader+reader+=+new+StreamReader(fileStream))
{
++++string+line+=+reader.ReadLine();
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1660252|使用System.IO.FileStream和System.IO.StreamReader。您也可以使用System.IO.BinaryReader或System.IO.BinaryWriter。|unstyled|offset|length|1660253|entityMap|0|LINK|mutability|MUTABLE|url|https://learn.microsoft.com/en-us/dotnet/core/api/system.io.filestream|1|https://learn.microsoft.com/en-us/dotnet/core/api/system.io.streamreader|2|https://learn.microsoft.com/en-us/dotnet/core/api/system.io.binaryreader|3|https://learn.microsoft.com/en-us/dotnet/core/api/system.io.binarywriter^0|0|2|K|0|N|M|1|1G|M|2|23|M|3|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|X|8|@]|9|@$G|Y|H|Z|1|10]|$G|11|H|12|1|13]|$G|14|H|15|1|16]|$G|17|H|18|1|19]]|A|$]]|$1|I|3|-4|5|F|7|1A|8|@]|9|@]|A|$]]]|J|$K|$5|L|M|N|A|$O|P]]|Q|$5|L|M|N|A|$O|R]]|S|$5|L|M|N|A|$O|T]]|U|$5|L|M|N|A|$O|V]]]]

<pre><code>FileStream fileStream = new FileStream("file.txt", FileMode.Open);
using (StreamReader reader = new StreamReader(fileStream))
{
 string line = reader.ReadLine();
}
</code></pre>

Using the <a href="https://learn.microsoft.com/en-us/dotnet/core/api/system.io.filestream" rel="noreferrer">System.IO.FileStream</a> and <a href="https://learn.microsoft.com/en-us/dotnet/core/api/system.io.streamreader" rel="noreferrer">System.IO.StreamReader</a>. You can use <a href="https://learn.microsoft.com/en-us/dotnet/core/api/system.io.binaryreader" rel="noreferrer">System.IO.BinaryReader</a> or <a href="https://learn.microsoft.com/en-us/dotnet/core/api/system.io.binarywriter" rel="noreferrer">System.IO.BinaryWriter</a> as well.

blocks|key|1660284|text|写：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1660285|using+(System.IO.StreamWriter+file+=
new+System.IO.StreamWriter(System.IO.File.Create(filePath).Dispose()))
{
++++file.WriteLine("your+text+here");
}|code-block|syntax|javascript|1660286|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

To write:

<pre><code>using (System.IO.StreamWriter file =
new System.IO.StreamWriter(System.IO.File.Create(filePath).Dispose()))
{
 file.WriteLine("your text here");
}
</code></pre>

blocks|key|492756|text|Net+2.1中的工作|type|unstyled|depth|inlineStyleRanges|entityRanges|data|492757|++++var+file+=+Path.Combine(Directory.GetCurrentDirectory(),+"wwwroot",+"email",+"EmailRegister.htm");

++++string+SendData+=+System.IO.File.ReadAllText(file);|code-block|syntax|javascript|492758|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Works in Net Core 2.1

<pre><code> var file = Path.Combine(Directory.GetCurrentDirectory(), "wwwroot", "email", "EmailRegister.htm");

 string SendData = System.IO.File.ReadAllText(file);
</code></pre>

blocks|key|494830|text|使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|494831|File.ReadAllLines("My+textfile.txt");|code-block|syntax|javascript|494832|参考资料：https://msdn.microsoft.com/pt-br/library/s2tte0y1(v=vs.110).aspx|offset|length|494833|entityMap|0|LINK|mutability|MUTABLE|url|https://msdn.microsoft.com/pt-br/library/s2tte0y1(v=vs.110).aspx^0|0|0|5|1S|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

Use:

<pre><code>File.ReadAllLines("My textfile.txt");
</code></pre>

Reference: <a href="https://msdn.microsoft.com/pt-br/library/s2tte0y1(v=vs.110).aspx" rel="noreferrer">https://msdn.microsoft.com/pt-br/library/s2tte0y1(v=vs.110).aspx</a>

blocks|key|494891|text|用于将任何文本写入文件。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|494892|public+static+void+WriteToFile(string+DirectoryPath,string+FileName,string+Text)
++++{
++++++++//Check+Whether+directory+exist+or+not+if+not+then+create+it
++++++++if(!Directory.Exists(DirectoryPath))
++++++++{
++++++++++++Directory.CreateDirectory(DirectoryPath);
++++++++}

++++++++string+FilePath+=+DirectoryPath+%2B+"\\"+%2B+FileName;
++++++++//Check+Whether+file+exist+or+not+if+not+then+create+it+new+else+append+on+same+file
++++++++if+(!File.Exists(FilePath))
++++++++{
++++++++++++File.WriteAllText(FilePath,+Text);
++++++++}
++++++++else
++++++++{
++++++++++++Text+=+$"{Environment.NewLine}{Text}";
++++++++++++File.AppendAllText(FilePath,+Text);
++++++++}
++++}|code-block|syntax|javascript|494893|用于从文件中读取文本|494894|public+static+string+ReadFromFile(string+DirectoryPath,string+FileName)
++++{
++++++++if+(Directory.Exists(DirectoryPath))
++++++++{
++++++++++++string+FilePath+=+DirectoryPath+%2B+"\\"+%2B+FileName;
++++++++++++if+(File.Exists(FilePath))
++++++++++++{
++++++++++++++++return+File.ReadAllText(FilePath);
++++++++++++}
++++++++}
++++++++return+"";
++++}|494895|这里供参考，这是官方的microsoft链接。|offset|length|494896|entityMap|0|LINK|mutability|MUTABLE|url|https://learn.microsoft.com/en-us/dotnet/api/system.io.file.writealltext?view=netframework-4.8^0|0|0|0|0|6|1|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|10|8|@]|9|@$M|11|N|12|1|13]]|A|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

For writing any Text to a file.

<pre><code>public static void WriteToFile(string DirectoryPath,string FileName,string Text)
 {
 //Check Whether directory exist or not if not then create it
 if(!Directory.Exists(DirectoryPath))
 {
 Directory.CreateDirectory(DirectoryPath);
 }

 string FilePath = DirectoryPath + "\\" + FileName;
 //Check Whether file exist or not if not then create it new else append on same file
 if (!File.Exists(FilePath))
 {
 File.WriteAllText(FilePath, Text);
 }
 else
 {
 Text = $"{Environment.NewLine}{Text}";
 File.AppendAllText(FilePath, Text);
 }
 }
</code></pre>

For reading a Text from file

<pre><code>public static string ReadFromFile(string DirectoryPath,string FileName)
 {
 if (Directory.Exists(DirectoryPath))
 {
 string FilePath = DirectoryPath + "\\" + FileName;
 if (File.Exists(FilePath))
 {
 return File.ReadAllText(FilePath);
 }
 }
 return "";
 }
</code></pre>

For Reference here <a href="https://learn.microsoft.com/en-us/dotnet/api/system.io.file.writealltext?view=netframework-4.8" rel="nofollow noreferrer">this</a> is the official microsoft document link.

blocks|key|1462292|text|++++public+static+void+Copy(String+SourceFile,+String+TargetFile)
++++{

++++++++FileStream+fis+=+null;
++++++++FileStream+fos+=+null;

++++++++++++try
++++++++++++{
++++++++++++++++Console.Write("##+Try+No.+"+%2B+a+%2B+"+:+(Write+from+"+%2B+SourceFile+%2B+"+to+"+%2B+TargetFile+%2B+")\n");

++++++++++++++++fis+=+new+FileStream(SourceFile,+FileMode.Open,+FileAccess.ReadWrite);
++++++++++++++++fos+=+new+FileStream(TargetFile,+FileMode.Create,+FileAccess.ReadWrite);

++++++++++++++++int+intbuffer+=+5242880;
++++++++++++++++byte[]+b+=+new+byte[intbuffer];

++++++++++++++++int+i;
++++++++++++++++while+((i+=+fis.Read(b,+0,+intbuffer))+>+0)
++++++++++++++++{
++++++++++++++++++++fos.Write(b,+0,+i);
++++++++++++++++}

++++++++++++++++Console.Write("Writing+file+:+"+%2B+TargetFile+%2B+"+is+successful.\n");

++++++++++++++++break;
++++++++++++}
++++++++++++catch+(Exception+e)
++++++++++++{
++++++++++++++++Console.Write("Writing+file+:+"+%2B+TargetFile+%2B+"+is+unsuccessful.\n");
++++++++++++++++Console.Write(e);
++++++++++++}
++++++++++++finally
++++++++++++{
++++++++++++++++if+(fis+!=+null)
++++++++++++++++{
++++++++++++++++++++fis.Close();
++++++++++++++++}
++++++++++++++++if+(fos+!=+null)
++++++++++++++++{
++++++++++++++++++++fos.Close();
++++++++++++++++}
++++++++++++}
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1462293|上面的代码将读取一个大文件并写入一个新的大文件。"intbuffer“值可以设置为1024倍。虽然源文件和目标文件都是打开的，但它按字节读取大文件，并按字节写入新的目标文件。它不会消失在记忆中。|unstyled|1462294|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> public static void Copy(String SourceFile, String TargetFile)
 {

 FileStream fis = null;
 FileStream fos = null;

 try
 {
 Console.Write("## Try No. " + a + " : (Write from " + SourceFile + " to " + TargetFile + ")\n");

 fis = new FileStream(SourceFile, FileMode.Open, FileAccess.ReadWrite);
 fos = new FileStream(TargetFile, FileMode.Create, FileAccess.ReadWrite);

 int intbuffer = 5242880;
 byte[] b = new byte[intbuffer];

 int i;
 while ((i = fis.Read(b, 0, intbuffer)) &gt; 0)
 {
 fos.Write(b, 0, i);
 }

 Console.Write("Writing file : " + TargetFile + " is successful.\n");

 break;
 }
 catch (Exception e)
 {
 Console.Write("Writing file : " + TargetFile + " is unsuccessful.\n");
 Console.Write(e);
 }
 finally
 {
 if (fis != null)
 {
 fis.Close();
 }
 if (fos != null)
 {
 fos.Close();
 }
 }
 }
</code></pre>

The code above will read a big file and write to a new big file. The "intbuffer" value can be set in multiple of 1024. While both source and target file are open, it reads the big file by bytes and write to the new target file by bytes. It will not go out of memory.

What are the options to read/write files in .Net Core?

I am working on my first .Net Core app and looking for 
<code>File.Read*</code>/<code>File.Write*</code> functions (<code>System.IO</code> from <code>.Net</code>) alternatives.

How to read/write files in .Net Core?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

文章

问答

视频

学习中心

腾讯云实验室

直播

竞赛

腾讯云代码分析专区

腾讯iOA零信任安全管理系统专区

腾讯云架构师技术同盟交流圈

腾讯云数据库专区

腾讯云顾问专区

腾讯云原生专区

腾讯混元专区

腾讯云TCE专区

腾讯云Lighthouse专区

腾讯云HAI专区

腾讯云Edgeone专区

腾讯云存储专区

腾讯云智能专区

腾讯轻联专区 

腾讯云开发专区

TAPD专区

腾讯轻量云游戏服专区

腾讯云最具价值专家

腾讯云架构师技术同盟

腾讯云创作之星

腾讯云开发者先锋

腾讯云代码助手

云原生构建

TAPD 敏捷项目管理

Cloud Studio

SDK中心

API中心

命令行工具

涵盖代码开发、场景应用、自动测试全流程，助你从零构建专属AI助手

一站式MCP教程库，解锁AI应用新玩法

在.Net核心中读取/写入文件的选项是什么？我正在开发我的第一个.Net核心应用程序，并寻找File.Read*/File.Write*函数(来自.Net的System.IO)替代方案。

问如何在.Net内核中读写文件？
EN

回答 7

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何在.Net内核中读写文件？EN

回答 7

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何在.Net内核中读写文件？
EN