一方面，Invoke-WebRequest引发的错误永远不会被捕获在您的代码中。另外，代码段的最后一行将替换catch块可能已分配给$StatusCode的所有内容。将两个语句都移到try块中。我还要添加另一个catch来处理可能发生的其他异常。

更改此：

if ($response = (Invoke-WebRequest @Params -ErrorAction Stop)) {
    try {
        $Token = (($response.Content) | ConvertFrom-Json).Token
    } catch [System.Net.WebException] {
        $StatusCode = "Status Code: $($_.Exception.Response.StatusCode.Value__) ";
        $Message = " Message: $($_.Exception.Message)"
    }
}

$StatusCode = "Status Code: $([int]$response.BaseResponse.statusCode)"

对此：

try {
    $response = (Invoke-WebRequest @Params -ErrorAction Stop)
    $Token = (($response.Content) | ConvertFrom-Json).Token
    $StatusCode = "Status Code: $([int]$response.BaseResponse.statusCode)"
} catch [System.Net.WebException] {
    $StatusCode = "Status Code: $($_.Exception.Response.StatusCode.Value__) "
    $Message = " Message: $($_.Exception.Message)"
} catch {
    $StatusCode = 0
    $Message = " Message: $($_.Exception.Message)"
    # alternatively re-throw the exception by uncommenting below line
    #throw
}

如果您只想要状态码200和401，而又不想要其他任何状态码，则可以执行以下操作：

try {
    $response = (Invoke-WebRequest @Params -ErrorAction Stop)
    $Token = (($response.Content) | ConvertFrom-Json).Token
    $StatusCode = "Status Code: $([int]$response.BaseResponse.statusCode)"
} catch [System.Net.WebException] {
    if ($_.Exception.Response.StatusCode.Value__ -eq 401) {
        $StatusCode = "Status Code: $($_.Exception.Response.StatusCode.Value__) "
        $Message = " Message: $($_.Exception.Message)"
    } else {
        throw
    }
} catch {
    throw
}