c# - 将字符串从数组转换为 int

Question

我试图打印出数组元素的确切位置，但结果很短

string[] ocean = { "Beebo", "Jeff","Arthur", "Nemo", "Dory" };

foreach(string fish in ocean)
{
    if (fish == "Nemo")
    {
        Console.WriteLine("We found Nemo on position {0}!",int.Parse(fish));
        return;
    }
}

Console.WriteLine("He was not here");

我需要将 {0} 标记替换为该元素的数组索引(在本例中为 3)，但我在 int.Parse(fish) 处失败，这显然不起作用

Answer 1

实现此功能的最简单方法是切换到 for 循环

for(int i = 0; i < ocean.Length; i++)
{
    if (ocean[i] == "Nemo")
    {
        Console.WriteLine("We found Nemo on position {0}!", i);
        return;
    }
}
Console.WriteLine("He was not here");

或者，您可以在 foreach 中跟踪索引

int index = 0;
foreach(string fish in ocean)
{
    if (fish == "Nemo")
    {
        Console.WriteLine("We found Nemo on position {0}!", index);
        return;
    }

    index++;
}
Console.WriteLine("He was not here");

或者您可以完全避免循环并使用Array.IndexOf。如果没有找到该值，则返回-1。

int index = Array.IndexOf(ocean, "Nemo");
if(index >= 0)
    Console.WriteLine("We found Nemo on position {0}!", index);
else
    Console.WriteLine("He was not here");

这是一个 Linq 解决方案

var match = ocean.Select((x, i) => new { Value = x, Index = i })
    .FirstOrDefault(x => x.Value == "Nemo");
if(match != null)
    Console.WriteLine("We found Nemo on position {0}!", match.Index);
else
    Console.WriteLine("He was not here");