blocks|key|1158049|text|using+(FileStream+fs+=+File.OpenRead("file.txt"))
{
++++BinaryReader+reader+=+new+BinaryReader(fs);

++++int+intVal+=+reader.ReadInt32();
++++float+floatVal+=+reader.ReadSingle();
++++string+stringVal+=+reader.ReadString();
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1158050|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>using (FileStream fs = File.OpenRead("file.txt"))
{
 BinaryReader reader = new BinaryReader(fs);

 int intVal = reader.ReadInt32();
 float floatVal = reader.ReadSingle();
 string stringVal = reader.ReadString();
}
</code></pre>

blocks|key|1373253|text|试着这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1373254|http://stevedonovan.blogspot.com/2005/04/reading-numbers-from-file-in-c.html|offset|length|1373255|我想读一篇c#教程，在提问之前对整个画面有个大概的了解会很有用|1373256|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|24|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@$D|Q|E|R|1|S]]|A|$]]|$1|F|3|G|5|6|7|T|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|U|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|C]]]]

Try someting like this: 

<a href="http://stevedonovan.blogspot.com/2005/04/reading-numbers-from-file-in-c.html" rel="nofollow noreferrer">http://stevedonovan.blogspot.com/2005/04/reading-numbers-from-file-in-c.html</a>

IMHO Maybe to read a c# tutorial it will be really useful to have the whole picture in mind before asking

blocks|key|1158148|text|这不完全是您问题的答案，但如果您是C#新手，则需要考虑的一个想法是:如果您使用自定义文本文件来读取一些配置参数，则可能需要检查.NET中的序列化主题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1158149|XML序列化提供了一种写入和读取XML格式文件的简单方法。例如，如果您有一个配置类，如下所示：|1158150|public+class+Configuration
{
+++public+int+intVal+{+get;+set;+}
+++public+float+floatVal+{+get;+set;+}
+++public+string+stringVal+{+get;+set;+}
}|code-block|syntax|javascript|1158151|您可以简单地使用XmlSerializer类保存并加载它：|offset|length|style|CODE|1158152|public+void+Save(Configuration+config,+string+fileName)
{
+++XmlSerializer+xml+=+new+XmlSerializer(typeof(Configuration));
+++using+(StreamWriter+sw+=+new+StreamWriter(fileName))
+++{
+++++++xml.Serialize(sw,+config);
+++}
}

public+Configuration+Load(string+fileName)
{
+++XmlSerializer+xml+=+new+XmlSerializer(typeof(Configuration));
+++using+(StreamReader+sr+=+new+StreamReader(fileName))
+++{
+++++++return+(Configuration)xml.Deserialize(sr);
+++}
}|1158153|上面定义的Save方法将创建一个包含以下内容的文件：|1158154|<Configuration>
++++<intVal>0</intVal>
++++<floatVal>0.0</floatVal>
++++<stringVal></stringVal>
</Configuration>|1158155|这种方法的好处是，如果Configuration类发生更改，则不需要更改Save和Load方法。|1158156|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.xml.serialization.xmlserializer.aspx^0|0|0|0|8|D|8|D|0|0|0|5|4|0|0|B|D|10|4|15|4|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|15|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|16|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|17|8|@$K|18|L|19|M|N]]|9|@$K|1A|L|1B|1|1C]]|A|$]]|$1|O|3|P|5|F|7|1D|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|1E|8|@$K|1F|L|1G|M|N]]|9|@]|A|$]]|$1|S|3|T|5|F|7|1H|8|@]|9|@]|A|$G|H]]|$1|U|3|V|5|6|7|1I|8|@$K|1J|L|1K|M|N]|$K|1L|L|1M|M|N]|$K|1N|L|1O|M|N]]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1P|8|@]|9|@]|A|$]]]|X|$Y|$5|Z|10|11|A|$12|13]]]]

Not exactly the answer to your question, but just an idea to consider if you are new to C#: If you are using a custom text file to read some configuration parameters, you might want to check XML serialization topics in .NET.

XML serialization provides a simple way to write and read XML formatted files. For example, if you have a configuration class like this:

<pre><code>public class Configuration
{
 public int intVal { get; set; }
 public float floatVal { get; set; }
 public string stringVal { get; set; }
}
</code></pre>

you can simply save it and load it using the <a href="http://msdn.microsoft.com/en-us/library/system.xml.serialization.xmlserializer.aspx" rel="nofollow noreferrer"><code>XmlSerializer</code></a> class:

<pre><code>public void Save(Configuration config, string fileName)
{
 XmlSerializer xml = new XmlSerializer(typeof(Configuration));
 using (StreamWriter sw = new StreamWriter(fileName))
 {
 xml.Serialize(sw, config);
 }
}

public Configuration Load(string fileName)
{
 XmlSerializer xml = new XmlSerializer(typeof(Configuration));
 using (StreamReader sr = new StreamReader(fileName))
 {
 return (Configuration)xml.Deserialize(sr);
 }
}
</code></pre>

<code>Save</code> method as defined above will create a file with the following contents:

<pre><code>&lt;Configuration&gt;
 &lt;intVal&gt;0&lt;/intVal&gt;
 &lt;floatVal&gt;0.0&lt;/floatVal&gt;
 &lt;stringVal&gt;&lt;/stringVal&gt;
&lt;/Configuration&gt;
</code></pre>

Good thing about this approach is that you don't need to change the <code>Save</code> and <code>Load</code> methods if your <code>Configuration</code> class changes.

blocks|key|1373350|text|我喜欢使用StreamReader快速方便地访问文件。就像..。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1373351|++String+file+=+"data_file.txt";++++
++StreamReader+dataStream+=+new+StreamReader(file);+++
++string+datasample;
++while+((datasample+=+dataStream.ReadLine())+!=+null)
++{

+++++//+datasample+has+the+current+line+of+text+-+write+it+to+the+console.
+++++Console.Writeline(datasample);
++}|code-block|syntax|javascript|1373352|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|$]]

I like using the StreamReader for quick and easy file access. Something like....

<pre><code> String file = "data_file.txt"; 
 StreamReader dataStream = new StreamReader(file); 
 string datasample;
 while ((datasample = dataStream.ReadLine()) != null)
 {

 // datasample has the current line of text - write it to the console.
 Console.Writeline(datasample);
 }
</code></pre>

blocks|key|1158243|text|C#似乎没有像C%2B%2B那样的格式化流阅读器(我很高兴被纠正)。因此，Jon+Skeet将内容读取为字符串并将其解析为所需类型的方法将是最好的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1158244|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

C# doesn't seem to have formatted stream readers like C++ (I would be happy to be corrected). So Jon Skeet approach of reading the contents as string and parsing them to the desired type would be the best.

blocks|key|1158277|text|下面是我从文本文件中读取数字的代码。它演示了从文本文件"2+3+5+7+...“中读取数字的概念。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1158278|public+class+NumberReader+
{
++++StreamReader+reader;

++++public+NumberReader(StreamReader+reader)
++++{
++++++++this.reader+=+reader;
++++}

++++public+UInt64+ReadUInt64()
++++{
++++++++UInt64+result+=+0;

++++++++while+(!reader.EndOfStream)
++++++++{
++++++++++++int+c+=+reader.Read();
++++++++++++if+(char.IsDigit((char)+c))
++++++++++++{
++++++++++++++++result+=+10+*+result+%2B+(UInt64)+(c+-+'0');
++++++++++++}
++++++++++++else
++++++++++++{
++++++++++++++++break;
++++++++++++}
++++++++}

++++++++return+result;
++++}
}|code-block|syntax|javascript|1158279|下面是使用此类的示例代码：|1158280|using+(StreamReader+reader+=+File.OpenText("numbers.txt"))
{+
++++NumberReader+numbers+=+new+NumberReader(reader);

++++while+(!+reader.EndOfStream)
++++{
++++++++ulong+lastNumber+=+numbers.ReadUInt64();
++++}
}|1158281|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Here is my code to read numbers from the text file. It demonstrates the concept of reading numbers from text file "2 3 5 7 ..."

<pre><code>public class NumberReader 
{
 StreamReader reader;

 public NumberReader(StreamReader reader)
 {
 this.reader = reader;
 }

 public UInt64 ReadUInt64()
 {
 UInt64 result = 0;

 while (!reader.EndOfStream)
 {
 int c = reader.Read();
 if (char.IsDigit((char) c))
 {
 result = 10 * result + (UInt64) (c - '0');
 }
 else
 {
 break;
 }
 }

 return result;
 }
}
</code></pre>

Here is sample code to use this class:

<pre><code>using (StreamReader reader = File.OpenText("numbers.txt"))
{ 
 NumberReader numbers = new NumberReader(reader);

 while (! reader.EndOfStream)
 {
 ulong lastNumber = numbers.ReadUInt64();
 }
}
</code></pre>

This is something that should be very simple. I just want to read numbers and words from a text file that consists of tokens separated by white space. How do you do this in C#? For example, in C++, the following code would work to read an integer, float, and word. I don't want to have to use a regex or write any special parsing code.

<pre><code>ifstream in("file.txt");
int int_val;
float float_val;
string string_val;
in &gt;&gt; int_val &gt;&gt; float_val &gt;&gt; string_val;
in.close();
</code></pre>

Also, whenever a token is read, no more than one character beyond the token should be read in. This allows further file reading to depend on the value of the token that was read. As a concrete example, consider

<pre><code>string decider;
int size;
string name;

in &gt;&gt; decider;
if (decider == "name")
 in &gt;&gt; name;
else if (decider == "size")
 in &gt;&gt; size;
else if (!decider.empty() &amp;&amp; decider[0] == '#')
 read_remainder_of_line(in);
</code></pre>

Parsing a binary PNM file is also a good example of why you would like to stop reading a file as soon as a full token is read in.

Read numbers from a text file in C#

这应该是非常简单的事情。我只想从一个由空格分隔的标记组成的文本文件中读取数字和单词。在C#中如何做到这一点？例如，在C++中，下面的代码可以读取整数、浮点数和单词。我不想使用正则表达式或编写任何特殊的解析代码。ifstream in("file.txt");int int_val;float float_val;str...

问在C#中从文本文件中读取数字
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