VB.NET

String.Join(",", myArray.Where(Function(s) Not String.IsNullOrEmpty(s)))

C#

String.Join(",", myArray.Where(s => !string.IsNullOrEmpty(s)))

You can do it like this in CSharp:

String.Join(",", arr.Where(s => !String.IsNullOrEmpty(s)));

要在.NET 2.0（无LINQ）中执行此操作，例如，对于SQL-Server ReportingServices，无需为其编写函数：
VB.NET

Dim a As String = "", b As String = "b", c As String = "", d As String = "d", e As String = ""
Dim lala As String = String.Join(" / ", String.Join(vbBack, New String() {a, b, c, d, e}).Split(New Char() {ControlChars.Back}, System.StringSplitOptions.RemoveEmptyEntries))

System.Console.WriteLine(lala)

C#（对于那些从谷歌登陆，而不是搜索VB .NET）

string a = "", b = "b", c = "", d = "d", e = "";
string lala = string.Join(" / ",
    string.Join("\u0008", 
        new string[] { a, b, c, d, e }
    ).Split(new char[] { '\u0008' }, System.StringSplitOptions.RemoveEmptyEntries)
);

System.Console.WriteLine(lala);

这里假设字符串中没有出现退格键（通常应该是真的，因为不能简单地通过键盘输入这个字符）。
此外，如果您从数据库中获取值，则会更加简单，因为您可以直接在SQL中执行此操作：
PostgreSQL和MySQL：

SELECT 
    concat_ws(' / '
        , NULLIF(searchTerm1, '')
        , NULLIF(searchTerm2, '')
        , NULLIF(searchTerm3, '')
        , NULLIF(searchTerm4, '')
    ) AS RPT_SearchTerms;

即使有了出色的MS-SQL-Server，也有可能（PS：这是讽刺）：

DECLARE @in_SearchTerm1 nvarchar(100) 
DECLARE @in_SearchTerm2 nvarchar(100) 
DECLARE @in_SearchTerm3 nvarchar(100) 
DECLARE @in_SearchTerm4 nvarchar(100) 

SET @in_SearchTerm1 = N'a'
SET @in_SearchTerm2 = N''
SET @in_SearchTerm3 = N'c'
SET @in_SearchTerm4 = N''

SELECT 
    COALESCE
    (
        STUFF
        (
            (
                SELECT ' / ' + RPT_SearchTerm AS [text()]
                FROM 
                (
                                  SELECT NULLIF(@in_SearchTerm1, N'') AS RPT_SearchTerm, 1 AS RPT_Sort 
                        UNION ALL SELECT NULLIF(@in_SearchTerm2, N'') AS RPT_SearchTerm, 2 AS RPT_Sort  
                        UNION ALL SELECT NULLIF(@in_SearchTerm3, N'') AS RPT_SearchTerm, 3 AS RPT_Sort 
                        UNION ALL SELECT NULLIF(@in_SearchTerm4, N'') AS RPT_SearchTerm, 4 AS RPT_Sort 
                ) AS tempT 
                WHERE RPT_SearchTerm IS NOT NULL 
                ORDER BY RPT_Sort 
                FOR XML PATH(N''), TYPE 
            ).value('.', 'nvarchar(MAX)') 
            ,1
            ,3
            ,N''
        )
        ,N''
    ) AS RPT_SearchTerms

请尝试以下操作：

var finalString = String.Join(",", ExampleArrayOfObjects.Where(x => !String.IsNullOrEmpty(x.TestParameter)).Select(x => x.TestParameter));

另一种选择是使用LINQ方便的空过滤器进行过滤：

String.Join(",", myArray.OfType<string>())

这适用于VB.NET
Join(*yourArray*.Where(Function(s) Not String.IsNullOrEmpty(s)).ToArray(), *yourDelimiter*)