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优化VB.NET应用程序的性能(1) |
1) 整数除法运算符 和 /
比 / 快10倍 （如果是整数除法并且不需要保留小数）
(2) 赋值运算符 a +=b 和 a = a+b
+= 快
(3) 串联运算符 & 和 +
用 & 快
（来源：http://www.devcity.net/newsletter/archive/devcity/devcity20040315.htm#ni030)
.NET Pro: Optimize the Performance of VB.NET Applications
Operators
by Mike McIntyre
Division: V.S. /
Divide integral values with the (back slash) operator when you do not need decimal points or fractional values. The operator is the integral division operator and it is up to 10 times faster than the / (forward slash) operator.
Compound Assignment Operators: a += b V.S a = a + b
Compound assignment statements first perform an operation on an argument before assigning it to another argument. Example:
a += b
In the example above, b is added to the value of a, and that new value is then assigned to a. Compound assignment operators are more concise than their constituent operators (separate + and =). Compare the statement above to the one below. The statement above is a shorthand equivalent of the statement below.
a = a + b
Compound assignment operators are faster. If you are operating on an expression instead of a single variable, for example an array element, you can achieve a significant improvement with compound assignment operators.
Compound assignment operators for numbers:
^=
*=
/=
=
+=
-=
Compound operator for strings: &= Example:
Dim a As String = "First " a &= "Name"
Result: First Name
Concatenation: & V.S. +
Use the & concatenation operator instead of the + operator to increase the speed of concatenations. Performance of the & and + operators are only equivalent if both operands are type String. If not, the + operator is late bound and must perform type checking and conversions.
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