直到自己親自測試了才對他們有所了解，以前就知道用最后面那個，因為怕轉化出錯，所以就用它比較安全。
1.int ：(int)變量，C#默認整型為int32；(不支持bool轉化)
2.int.Parse(string sParameter) 4個構造函數，參數類型只支持string類型；
3.Convert.ToInt32()支持的類型是object；
事例：
using System;
using System.Collections.Generic;
using System.Text;
namespace IntegerSample
{
public class Program
{
private enum eNumber { Man = 1, Woman = 2 };
private static char cNumber = e ;
private static byte btNumber = 12;
private static long lNumber = 12345;
private static double dNumber = 12.34d;
private static decimal dlNumber = 4.5m;
private static bool bNumber = true;
private static string str = null;
private static string str1 = "";
private static string str2 = "123";
private static string str3 = "Hello";
public static void TransformByInt()
{
Console.WriteLine("{0} TransformByInt Into {1}", eNumber.Man, (int)eNumber.Man);
Console.WriteLine("{0} TransformByInt Into {1}", cNumber, (int)cNumber);
Console.WriteLine("{0} TransformByInt Into {1}", btNumber, (int)btNumber);
Console.WriteLine("{0} TransformByInt Into {1}", lNumber, (int)lNumber);
Console.WriteLine("{0} TransformByInt Into {1}", dNumber, (int)dNumber);
Console.WriteLine("{0} TransformByInt Into {1}", dlNumber, (int)dlNumber);
//Console.WriteLine("{0} TransformByInt Into {1}", bNumber, (int)bNumber);
//Console.WriteLine("{0} TransformByInt Into {1}", str1, (int)str);
}
// Result: 1
// Result：101
// Result: 12
// Result: 12345
// Result: 12
// Result: 4
// 無法將類型“bool”轉換為“int”
// 編譯錯誤，不能將string轉化為int
public static void TransformByIntParse()
{
try
{
Console.WriteLine("str {0}:", int.Parse(str));
Console.WriteLine("str1 {0}:", int.Parse(str1));
Console.WriteLine("str2 {0}:", int.Parse(str2));
