此範例示範如何聯結兩個逗號分隔檔案中的數據，這些檔案共享作為比對索引鍵的通用值。 如果您必須將來自兩個電子表格的數據，或從具有另一種格式的檔案，或從具有另一種格式的檔案將數據合併成新檔案，則這項技術會很有用。 您可以修改範例以使用任何類型的結構化文字。
建立數據檔
將下列幾行複製到名為 scores.csv 的檔案，並將它儲存至您的項目資料夾。 檔案代表電子表格數據。 第 1 欄是學生的標識碼，第 2 到 5 欄是測試分數。
111, 97, 92, 81, 60 112, 75, 84, 91, 39 113, 88, 94, 65, 91 114, 97, 89, 85, 82 115, 35, 72, 91, 70 116, 99, 86, 90, 94 117, 93, 92, 80, 87 118, 92, 90, 83, 78 119, 68, 79, 88, 92 120, 99, 82, 81, 79 121, 96, 85, 91, 60 122, 94, 92, 91, 91將下列幾行複製到名為 names.csv 的檔案，並將它儲存至您的項目資料夾。 這個檔案是包含學生姓氏、名字和學生編號的電子表格。
Omelchenko,Svetlana,111 O'Donnell,Claire,112 Mortensen,Sven,113 Garcia,Cesar,114 Garcia,Debra,115 Fakhouri,Fadi,116 Feng,Hanying,117 Garcia,Hugo,118 Tucker,Lance,119 Adams,Terry,120 Zabokritski,Eugene,121 Tucker,Michael,122
範例
Imports System.Collections.Generic
Imports System.Linq
Class JoinStrings
Shared Sub Main()
' Join content from spreadsheet files that contain
' related information. names.csv contains the student name
' plus an ID number. scores.csv contains the ID and a
' set of four test scores. The following query joins
' the scores to the student names by using ID as a
' matching key.
Dim names As String() = System.IO.File.ReadAllLines("../../../names.csv")
Dim scores As String() = System.IO.File.ReadAllLines("../../../scores.csv")
' Name: Last[0], First[1], ID[2], Grade Level[3]
' Omelchenko, Svetlana, 111, 2
' Score: StudentID[0], Exam1[1] Exam2[2], Exam3[3], Exam4[4]
' 111, 97, 92, 81, 60
' This query joins two dissimilar spreadsheets based on common ID value.
' Multiple from clauses are used instead of a join clause
' in order to store results of id.Split.
Dim scoreQuery1 = From name In names
Let n = name.Split(New Char() {","})
From id In scores
Let n2 = id.Split(New Char() {","})
Where Convert.ToInt32(n(2)) = Convert.ToInt32(n2(0))
Select n(0) & "," & n2(1) & "," & n2(2) & "," & n2(3) & "," & n2(4)
' Pass a query variable to a Sub and execute it there.
' The query itself is unchanged.
OutputQueryResults(scoreQuery1, "Merge two spreadsheets:")
' Keep console window open in debug mode.
Console.WriteLine("Press any key to exit.")
Console.ReadKey()
End Sub
Shared Sub OutputQueryResults(ByVal query As IEnumerable(Of String), ByVal message As String)
Console.WriteLine(System.Environment.NewLine & message)
For Each item As String In query
Console.WriteLine(item)
Next
Console.WriteLine(query.Count & " total names in list")
End Sub
End Class
' Output:
' Merge two spreadsheets:
' Omelchenko, 97, 92, 81, 60
' O'Donnell, 75, 84, 91, 39
' Mortensen, 88, 94, 65, 91
' Garcia, 97, 89, 85, 82
' Garcia, 35, 72, 91, 70
' Fakhouri, 99, 86, 90, 94
' Feng, 93, 92, 80, 87
' Garcia, 92, 90, 83, 78
' Tucker, 68, 79, 88, 92
' Adams, 99, 82, 81, 79
' Zabokritski, 96, 85, 91, 60
' Tucker, 94, 92, 91, 91
' 12 total names in list
