使用数组引用扩展符（[*]）来解构嵌套的数组。

在 ARM 模板中，数组引用扩展符（[*]）用于解构数组并扩展其元素。可使用此符号将嵌套的数组展开为平面数组。例如，假设我们有以下嵌套数组：

"myArray": [
    [ "a", "b", "c" ],
    [ "d", "e", "f" ]
]

若要将其展开为平面数组，可使用下面的表达式：

"flattenedArray": "[union(variables('myArray')[*])]"

在此示例中，“[*]” 在嵌套数组中引用了所有子数组。union() 函数将它们组合在一起并生成包含所有数组元素的平面数组。

完整的代码示例如下：

{
    "variables": {
        "myArray": [
            [ "a", "b", "c" ],
            [ "d", "e", "f" ]
        ]
    },
    "resources": [
        {
            "name": "example",
            "type": "Microsoft.Compute/virtualMachines",
            "apiVersion": "2021-04-01",
            "location": "[resourceGroup().location]",
            "properties": {
                "storageProfile": {
                    "dataDisks": [
                        {
                            "name": "disk1",
                            "diskSizeGB": 1,
                            "lun": 0,
                            "createOption": "Empty",
                            "caching": "None",
                            "diskIOPSReadWrite": 100,
                            "diffDiskSettings": {
                                "option": "Local"
                            },
                            "managedDisk": {
                                "storageAccountType": "Premium_LRS"
                            }
                        },
                        {
                            "name": "disk2",
                            "diskSizeGB": 2,
                            "lun": 1,
                            "createOption": "Empty",
                            "caching": "None",
                            "diskIOPSReadWrite": 200,
                            "diffDiskSettings": {
                                "option": "Local"
                            },
                            "managedDisk": {
                                "storageAccountType": "Premium_LRS"
                            }
                        }
                    ]
                }
            }
        }
    ]
}