如何在C＃中使用StreamReader（新手）

Question

I'm trying to read the contents of a text file, in this case a list of computer names (Computer1, computer2 etc,) and I thought that StreamReader would be what you would use but when I do the following:

StreamReader arrComputer = new StreamReader(FileDialog.filename)();

I got this exception:

The type or namespace name 'StreamReader' could not be found (are you missing a using directive or an assembly reference?)  

I'm very new to C# so I'm sure I'm making a newbie mistake.

Answer 1

You need to import the System.IO namespace. Put this at the top of your .cs file:

using System.IO;

Either that, or explicitly qualify the type name:

System.IO.StreamReader arrComputer = new System.IO.StreamReader(FileDialog.filename);

Answer 2

You'll need:

using System.IO;

At the top of the .cs file. If you're reading text content I recommend you use a TextReader which is bizarrely a base class of StreamReader.

try:

using(TextReader reader = new StreamReader(/* your args */))
{
}

The using block just makes sure it's disposed of properly.

Answer 3

try

using System.IO;


StreamReader arrComputer = new StreamReader(FileDialog.filename);

Answer 4

确保在项目的引用中有系统程序集，并将其添加到using部分：

using System.IO;

Answer 5

确保在usings声明中包含using System.IO

Answer 6

Make sure you are have "using System.IO;" at the top of your module. Also, you don't need the extra parenthesis at the end of "new StreamReader(FileDialog.filename)".

Answer 7

StreamReader is defined in System.IO. You either need to add

using System.IO;

to the file or change your code to:

System.IO.StreamReader arrComputer = new System.IO.StreamReader(FileDialog.filename);

Answer 8

You need to add a reference to the System.IO assembly. You can do this via the "My Project" properties page under the References tab.