Also talk about string. isnullorempty

Today, when browsing the devtopics blog, I found an article about string, which describes how to compare a method of string with an attribute when determining whether a string variable is null, to give a string variable's, which of the following expressions is faster?

1. String. isnullorempty (s)
2. S = NULL | S. Length = 0

If you guess the second one, you are right. It will be 15% faster than the string. isnullorempty method, but this is measured in one second per million!
Here is a simple example to compare two methods: Using System;

Namespace Stringnullempty
{
Class Program
{
Static   Void Main ( String [] ARGs)
{
Long Loop =   100000000 ;
String S =   Null ;
Long Option =   0 ;
Long Empties1 =   0 ;
Long Empties2 =   0 ;

Datetime time1 = Datetime. now;

For ( Long I =   0 ; I < Loop; I ++ )
{
Option = I %   4 ;
Switch (Option)
{
Case   0 :
S =   Null ;
Break ;
Case   1 :
S = String. empty;
Break ;
Case   2 :
S =   " H " ;
Break ;
Case   3 :
S =   " Hi " ;
Break ;
}
If (String. isnullorempty (s ))
Empties1 ++ ;
}

Datetime time2 = Datetime. now;

For ( Long I =   0 ; I < Loop; I ++ )
{
Option = I %   4 ;
Switch (Option)
{
Case   0 :
S =   Null ;
Break ;
Case   1 :
S = String. empty;
Break ;
Case   2 :
S =   " H " ;
Break ;
Case   3 :
S =   " Hi " ;
Break ;
}
If (S =   Null   | S. Length =   0 )
Empties2 ++ ;
}

Datetime time3 = Datetime. now;

Timespan span1 = Time2.subtract (time1 );
Timespan span2 = Time3.subtract (time2 );
Console. writeline ( " (String. isnullorempty (s): Time = {0} empties = {1} " ,
Span1, empties1 );
Console. writeline ( " (S = NULL | S. Length = 0): Time = {0} empties = {1} " ,
Span2, empties2 );
Console. Readline ();
}
}
}
The result is as follows:
(String. isnullorempty (s): Time = 00:00:06. 8437500 empties = 50000000
(S = NULL | S. Length = 0): Time = 00:00:05. 9218750 empties = 50000000