Cannot convert value of type 'String' to expected argument type

Question

I've created separate swift class in my project to collect all required information and validation as follow:

Config.swift

public class Config: NSObject {    
    func isValidEmail(testStr:String) -> Bool {
        let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"
        let range = testStr.rangeOfString(emailRegEx, options:.RegularExpressionSearch)
        let result = range != nil ? true : false
        return result
    }
}

But problem is when I call that function in anther class, I've faced following error:

if (Config.isValidEmail(txtEmail.text!))

Cannot convert value of type 'String' to expected argument type 'Config'

If I did like that as follow, got different error.

Config.isValidEmail(txtEmail.text)

Cannot convert value of type 'String?' to expected argument type 'Config'

I don't know why. Please help me how to solve.

Jeffery's correct about static, but since the lines describing what you tried won't compile, and seemingly should state there's no such method, I suggest you should carefully post more about the code you're trying that makes use of isValidEmail. — Feldur

Jeffery Thomas Jeffery Thomas · Accepted Answer · 2016-07-01T02:42:02

You care calling isValidEmail(_:) as a class method, but it's an instance method.

I think you want to make isValidEmail(_:) a class method.

public class Config: NSObject {
    static func isValidEmail(testStr:String) -> Bool {
        let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"
        let range = testStr.rangeOfString(emailRegEx, options:.RegularExpressionSearch)
        let result = range != nil ? true : false
        return result
    }
}

Note: the static specifier.

Cannot convert value of type 'String' to expected argument type

1 Answers