C# int与char或string拼接

using UnityEngine;
public class Test: MonoBehaviour{
    private void Start (){
		Debug.Log(',');//output:,
		Debug.Log(1+',');//output:45

		int intValue1=1+',';
		Debug.Log(intValue1);//output:45
		//int intValue2=1+",";//无法将类型"string"隐式转换为"int"

		//string str1=1+',';//无法将类型"int"隐式转换为"string"
		string str2=1+",";
		Debug.Log(str2);//output:1,
    }
}