如何使用linq讀取屬性值到xml

Question

這裏我使用的是xml文件。文件名是KMMiddleTier.xml

<?xml version="1.0" encoding="utf-8" standalone ="yes" ?> 
<KMMiddleTierSecurity> 
    <ConnectionKeys> 
    <ConnectionKey Key="DB_DEV" ConnectionString="Data source=TTDJS;Persist Security Info=False;Initial Catalog=TAMSdev;User Id={0};Password={1};" timeout="200" UserPasswordKey="DBUser"/> 
    <ConnectionKey Key="DB_QA" ConnectionString="Data source=YYSHDJ;Persist Security Info=False;Initial Catalog=TAMSqa;User Id={0};Password={1};" timeout="200" UserPasswordKey="DBUser"/> 
    <ConnectionKey Key="DB_PROD" ConnectionString="Data source=JSUDHS;Persist Security Info=False;Initial Catalog=TAMSDB;User Id={0};Password={1};" timeout="200" UserPasswordKey="DBUser"/> 
    <ConnectionKey Key="KMAUDIT" ConnectionString="data source=DISIS;FailOver Partner=LKWSQLTESTWS\LKWSQLTEST;Persist Security Info=False;Initial Catalog=KMAuditDEV;User Id={0};Password={1};Application Name='MiddleTier';Workstation ID='Thotsrc1'" UserPasswordKey="KMAuditUser"/> 
    </ConnectionKeys> 
</KMMiddleTierSecurity> 

我使用Windows窗體與vb.net

我想知道如何找回「DB_DEV」鍵連接字符串的值到一個變量。

請建議一些代碼

我想要的結果在某些變量"Data source=TTDJS;Persist Security Info=False;Initial Catalog=TAMSdev;User Id={0};Password={1};"

Answer 1

可以使用@attrname語法來引用屬性，所以：

Dim conStr = (
    From e In xml.<KMMiddleTierSecurity>.<ConnectionKeys>.<ConnectionKey> 
    Where e.@Key = "DB_DEV" 
    Select e.@ConnectionString 
).Single() 
Console.WriteLine(conStr) 

數據源= TTDJS; Persist Security Info = False; Initial Catalog = TAMSdev; User Id = {0}; Password = {1};