1. The line of the iteration file
Copy CodeThe code is as follows:
public static IEnumerable ReadLines (String fileName)
{
using (TextReader reader = File.OpenText (fileName))
{
String line;
if (line = reader. ReadLine ()) = null)
{
yield return line;
}
}
}
static void Main ()
{
foreach (String line in Iterator.readlines (""))
{
Console.WriteLine (line);
}
}
2. Using iterators and predicates to filter rows in a file
Copy CodeThe code is as follows:
public static IEnumerable where (IEnumerable SOURCE, predicate predicate)
{
if (Source = = NULL | | predicate = = NULL)
{
throw new ArgumentNullException ();
}
Return Whereimplemeter (source, predicate);
}
private static IEnumerable Whereimplemeter (IEnumerable SOURCE, predicate predicate)
{
foreach (T item in Source)
{
if (predicate (item))
{
Yield return item;
}
}
}
static void Main ()
{
IEnumerable lines = File.ReadAllLines (@ "Your File name");
predicate predicate = delegate (string line)
{
return line. StartsWith ("using");
};
foreach (String str in where (lines, predicate))
{
Console.WriteLine (str);
}
}
http://www.bkjia.com/phpjc/327537. HTML www.bkjia.com true http://www.bkjia.com/phpjc/327537.html techarticle 1. The line copy code code for the iteration file is as follows: public static Ienumerablestring readlines (String fileName) {using (TextReader reader = File.OpenText (fileName)) {string line; /span>
