Swift报错：Binary operator '=='无法应用于Any与Int类型操作数，求解决方案

Hey there! Let's break down what's causing this error and how to fix it quickly.

The core issue here is that your class_User.day array is typed as [Any] (since it's pulled directly from an API response). Swift is a strongly typed language, so it won't let you compare an Any value directly to an Int or String—it needs to know exactly what type it's working with first.

Solution 1: Safely cast elements to specific types first #

Since you're checking for values like 1 (Int) and "2" (String), we can add safe type casts to ensure we're comparing like types. Here's how to adjust your code:

for item in class_User.day {
    // Handle Int values
    if let i = item as? Int {
        if i == 1 {
            print(i)
            strdays += "1"
        } else if i == 2 {
            print(i)
            strdays += "- 2"
        }
    }
    // Handle String values (in case the API returns numbers as strings)
    else if let str = item as? String {
        if str == "1" {
            print(str)
            strdays += "1"
        } else if str == "2" {
            print(str)
            strdays += "- 2"
        }
    }
    // Optional: Catch unexpected types to avoid silent failures
    else {
        print("Skipping unsupported item type: \(type(of: item))")
    }
}

Solution 2: Use a switch statement for cleaner type checking #

If your API returns a mix of types and you want more readable code, a switch statement works great:

for item in class_User.day {
    switch item {
    case let i as Int where i == 1:
        print(i)
        strdays += "1"
    case let str as String where str == "2":
        print(str)
        strdays += "- 2"
    default:
        // Handle other values or unrecognized types here
        print("Unrecognized item: \(item)")
    }
}

Pro Tip: Fix the root cause at parsing time #

The best long-term fix is to avoid having an [Any] array entirely. When you parse the API response (using Codable, for example), define your class_User model with a specific type for the day property:

If the API returns an array of integers:

class class_User: Codable {
    let day: [Int]
    // Add other properties here...
}

If it returns an array of strings:

class class_User: Codable {
    let day: [String]
    // Add other properties here...
}

This way, you won't have to deal with type casting later on!

内容的提问来源于stack exchange，提问作者Vishal