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Question

具有执行查找的脚本。如果没有匹配项，如何将其更改为保留原始值。现在它留空了。

$PSDefaultParameterValues['*:Encoding'] = 'utf8'
$f1 = (Import-Csv 'A.txt' -Delimiter 'µ' -Header samname, id)
$f2 = (Import-Csv 'B.txt' -Delimiter 'µ' -Header samname, id)
$f1 | %{
    $samname = $_.samname
    $m = $f2 | ?{$_.samname -eq $samname}

    $_.id = $m.id
} 
$f1 | Export-Csv 'C.txt' -NoType

输入：

A.txt：

T3-F2-P8629-A1033-L999:µDue Date Calculation
T3-F2-P8629-A1063-L999:µDue Date Calculation
missing
missing

B.txt：

T3-F2-P8629-A1033-L999:µDue Date Calculation
T3-F2-P8629-A1063-L999:µMok. termino skaičiavimas
T3-F8-P8629-A1033-L999:µLast Modified Date Time
T3-F8-P8629-A1063-L999:µLast Modified Date Time

输出（C.txt）：

"T3-F2-P8629-A1033-L999:","Due Date Calculation"
"T3-F2-P8629-A1063-L999:","Mok. termino skaičiavimas"
"T3-F8-P8629-A1033-L999:",
"T3-F8-P8629-A1063-L999:",

预期输出：

"T3-F2-P8629-A1033-L999:","Due Date Calculation"
"T3-F2-P8629-A1063-L999:","Mok. termino skaičiavimas"
"T3-F8-P8629-A1033-L999:","Last Modified Date Time"
"T3-F8-P8629-A1063-L999:","Last Modified Date Time"