函数重载的两种作用

/// <summary>
/// 获取int数组的最大值
/// </summary>
/// <param name="intArray"></param>
/// <returns></returns>
public static int MaxValue(int[] intArray)
{
    int maxValue = intArray[0];
    for (int i = 0; i < intArray.Length; i++)
    {
        if (intArray[i] > maxValue) maxValue = intArray[i];
    }
    return maxValue;
}

/// <summary>
/// 获取double数组的最大值
/// </summary>
/// <param name="doubleArray"></param>
/// <returns></returns>
public static double MaxValue(double[] doubleArray)
{
    double maxValue = doubleArray[0];
    for (int i = 0; i < doubleArray.Length; i++)
    {
        if (doubleArray[i] > maxValue) maxValue = doubleArray[i];
    }
    return maxValue;
}

/// <summary>
/// 当字符串为空时返回默认值字符串
/// </summary>
/// <param name="filter"></param>
/// <returns></returns>
public static string ChkStringNull(string filter)
{
    return ChkStringNull(filter,"-");
}

/// <summary>
/// 当字符串为空时返回默认值字符串
/// </summary>
/// <param name="filter"></param>
/// <param name="defaultFilter"></param>
/// <returns></returns>
public static string ChkStringNull(string filter,string defaultFilter)
{
    if (string.Empty != filter && filter != null)
        return filter;
    else
        return defaultFilter;
}