取出两个时间差
秒数再在0到该秒数的间随机获取
个整数将其做为秒添加到较小时间上可以说实现上并没什么技术难点可以在数据类型边界条件上却需要格外注意比如将大于 
.Int32.MaxValue 或小于 .Int32.MinValue 值转成 
时如果直接在变量前加上类型名转换(()d)不会有有异常产生但得到值却是 .Int32.MinValue还有就是对于Math.Abs 思路方法当参数 value 等于 MinValue 将会引发 .OverflowException 异常
代码如下:
using ;
Yyw
{
public 
DateTimeHelper
{
/**//// <summary>
/// 获取随机时间
/// <remarks>
/// 由于Random 以当前系统时间做为种值,所以当快速运行多次该思路方法所得到结果可能相同,
/// 这时,你应该在外部
化 Random 例子并
GetRandomTime(DateTime time1, DateTime time2, Random random)
/// </remarks>
/// </summary>
/// <param name="time1"></param>
/// <param name="time2"></param>
/// <
s></s>
public 
DateTime GetRandomTime(DateTime time1, DateTime time2)
{
Random random = 
Random
;
GetRandomTime(time1, time2, random);
}
/**//// <summary>
/// 获取随机时间
/// </summary>
/// <param name="time1"></param>
/// <param name="time2"></param>
/// <param name="random"></param>
/// <s></s>
public DateTime GetRandomTime(DateTime time1, DateTime time2, Random random)
{
DateTime minTime = DateTime;
DateTime maxTime = DateTime;
.TimeSpan ts = .TimeSpan(time1.Ticks - time2.Ticks);
// 获取两个时间相隔秒数
double dTotalSecontds = ts.TotalSeconds;
iTotalSecontds = 0;
(dTotalSecontds > .Int32.MaxValue)
{
iTotalSecontds = .Int32.MaxValue;
}
(dTotalSecontds < .Int32.MinValue)
{
iTotalSecontds = .Int32.MinValue;
}
{
iTotalSecontds = ()dTotalSecontds;
}
(iTotalSecontds > 0)
{
minTime = time2;
maxTime = time1;
}
(iTotalSecontds < 0)
{
minTime = time1;
maxTime = time2;
}
{
time1;
}
maxValue = iTotalSecontds;
(iTotalSecontds <= .Int32.MinValue)
maxValue = .Int32.MinValue + 1;
i = random.Next(.Math.Abs(maxValue));
minTime.AddSeconds(i);
}
}
}测试代码:using ;
using NUnit.Framework;
Yyw
{
[TestFixture]
public DateTimeHelperFixture
{
/**//// <summary>
/// 边界测试
/// </summary>
[Test]
public void TestGetRandomTime
{
DateTime minTime = DateTime.MinValue;
DateTime maxTime = DateTime.MaxValue;
Random random = Random;
for ( i = 0; i < 10000; i
)
{
DateTime randomTime = DateTimeHelper.GetRandomTime(maxTime, minTime, random);
CheckResult(minTime, maxTime, randomTime);
}
for ( i = 0; i < 10000; i)
{
DateTime randomTime = DateTimeHelper.GetRandomTime(minTime, maxTime, random);
CheckResult(minTime, maxTime, randomTime);
}
}
private void CheckResult(DateTime minTime, DateTime maxTime, DateTime randomTime)
{
.TimeSpan ts1 = .TimeSpan(randomTime.Ticks - minTime.Ticks);
.TimeSpan ts2 = .TimeSpan(randomTime.Ticks - maxTime.Ticks);
Assert.IsTrue(ts1.Seconds >= 0 && ts2.Seconds <= 0);
}
}
}http://www.cnblogs.com/yyw84/archive/2006/09/07/497800.html
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