在swift 3.0中，您可以将整数更改为字符串，如下所示

let a:String = String(stringInterpolationSegment: 15)

另一种方法是

let number: Int = 15
let _numberInStringFormate: String = String(number)

//或任何整数来代替15

我正在使用这个简单的方法

字符串到Int:

 var a = Int()
var string1 = String("1")
a = string1.toInt()

和从Int到String:

var a = Int()
a = 1
var string1 = String()
 string1= "\(a)"

为了完整起见，你还可以使用:

let x = 10.description

或支持描述的任何其他值。

弦乐演奏

稍微讲讲性能 UI测试包在iPhone 7(真实设备)与iOS 14

let i = 0
lt result1 = String(i) //0.56s 5890kB
lt result2 = "\(i)" //0.624s 5900kB
lt result3 = i.description //0.758s 5890kB

import XCTest

class ConvertIntToStringTests: XCTestCase {
    let count = 1_000_000
    
    func measureFunction(_ block: () -> Void) {
        let metrics: [XCTMetric] = [
            XCTClockMetric(),
            XCTMemoryMetric()
        ]
        let measureOptions = XCTMeasureOptions.default
        measureOptions.iterationCount = 5
        
        measure(metrics: metrics, options: measureOptions) {
            block()
        }
    }

    func testIntToStringConstructor() {
        var result = ""
        measureFunction {
            for i in 0...count {
                result += String(i)
            }
        }
    }
    
    func testIntToStringInterpolation() {
        var result = ""
        measureFunction {
            for i in 0...count {
                result += "\(i)"
            }
        }
    }
    
    func testIntToStringDescription() {
        var result = ""
        measureFunction {
            for i in 0...count {
                result += i.description
            }
        }
    }
}

有多种方法:

var str1:String="\(23)"
var str2:String=String(format:"%d",234)

let Str = "12"
let num: Int = 0
num = Int (str)