String.IsNullOrEmpty官方示例

// This example demonstrates the String.IsNullOrEmpty() method
using System;

class Sample
{
    public static void Main()
    {
    string s1 = "abcd";
    string s2 = "";
    string s3 = null;

    Console.WriteLine("String s1 {0}.", Test(s1));
    Console.WriteLine("String s2 {0}.", Test(s2));
    Console.WriteLine("String s3 {0}.", Test(s3));
    }

    public static String Test(string s)
    {
    if (String.IsNullOrEmpty(s) == true)
        return "is null or empty";
    else
        return String.Format("(\"{0}\") is not null or empty", s);
    }
}
/*
This example produces the following results:

String s1 ("abcd") is not null or empty.
String s2 is null or empty.
String s3 is null or empty.

*/

String类提供的这个IsNullOrEmpty方法十分的优雅，英语就是graceful。String的话一般都会有""和null两种情况，如果自己写，用if(s=="" || s==Null)就不太美妙了。

Normal
0

7.8 磅
0
2

false
false
false

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