用扩展方法生成分割符字符串

使用扩展方法对IEnumerable<T>扩展,来生成分割符字符串.看这个方法:

/// <summary>
/// Get the delimited string.
/// </summary>
/// <typeparam name="T">T</typeparam>
/// <param name="list">The list.</param>
/// <param name="delimiter">The delimiter.</param>
/// <param name="action">The action.</param>
/// <returns>string</returns>
public static string ToDelimitedString<T>(this IEnumerable<T> list, string delimiter, Func<T, string> action)
{
    var sb = new System.Text.StringBuilder();
    foreach (var t in list)
    {
        sb.Append(action.Invoke(t));
        sb.Append(delimiter);
    }
    sb.Remove(sb.Length - delimiter.Length, delimiter.Length);

    return sb.ToString();
}

代码很简单,就不说了,来难证下,假设有以下类:

public class Person
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
}

UnitTest，这里是”,”分隔符，当然你可以用其它的：

/// <summary>
/// Tests the delimited string.
/// </summary>
/// <remarks>author:Petter Liu  http://wintersun.cnblogs.com </remarks>
[Test]
public void TestDelimitedString()
{
    var list = new List<Person>
                   {
                       new Person() {FirstName = "Petter", LastName = "Liu"},
                       new Person() {FirstName = "Tina", LastName = "Lin"},
                       new Person() {FirstName = "David", LastName = "Pan"},
                       new Person() {FirstName = "John", LastName = "Robert"}
                   };

    var result=list.ToDelimitedString(",", p => string.Format("{0} {1}", p.FirstName, p.LastName));

    System.Diagnostics.Debug.WriteLine(result);
    // Petter Liu,Tina Lin,David Pan,John Robert
}

用好扩展方法，能为我们省很多的代码量．

Author:PetterLiu    http://wintersun.cnblogs.com