C# 4 and .NET 4

eading and Writing to files ❘ 785
}
InitializeComponent();
}
}
private void button1_Click(object sender, EventArgs e)
{
textBox2.Text = File.ReadAllText(textBox1.Text);
}
code download ReadingFiles.sln
In building this example, the first step is to add the using statement to bring in the System.IO namespace.
From there, simply use the button1_Click event for the Send button on the form to populate the text
box with what comes back from the file. You can now access the file’s contents by using the File.
ReadAllText() method. As you can see, you can read files with a single statement. The ReadAllText()
method opens the specified file, reads the contents, and then closes the file. The return value of the
ReadAllText() method is a string containing the entire contents of the file specified. The result would be
something similar to what is shown in Figure 29-7.
figure 29-7
The File.ReadAllText() signature shown in the preceding example is of the following construction:
File.ReadAllText(FilePath);
The other option is to also specify the encoding of the file being read:
File.ReadAllText(FilePath, Encoding);
Using this signature allows you to specify the encoding to use when opening and reading the contents of the
file. Therefore, this means that you could do something like the following:
File.ReadAllText(textBox1.Text, Encoding.ASCII);
Some of the other options for opening and working with files include using the ReadAllBytes() and
the ReadAllLines() methods. The ReadAllBytes() method allows you to open a binary file and read
www.it-ebooks.info