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首页 - 经验之谈 - 短代码不一定效率高!
发表评论(0)作者:不详, 平台:VB6.0+Win98, 阅读:8808, 日期:2000-11-02
Shorter Visual Basic code isn注释:t always efficient code

In a previous tip, we showed you an object-oriented way to pass values
to form variables. To do so, we added property Get and Let statements
to the form注释:s underlying code module. This created a public property for
the form that you could set with code similar to

Form1.myProperty = "Fifty"

Many of you pointed out that as an alternative to the lengthy Get and
Let procedures we used in the tip, you could also simply declare a
form-level public variable, as in

Public myProperty as Integer

Given this declaration, you could then set and retrieve the property
using the same syntax we used above.  

While declaring the property in this manner is perfectly legal, it does
have a broader potential for errors than do Get and Let statements --
though it注释:s still better than using full-blown, application level,
global variables.

The problem occurs because under the shorter property declaration
scenario, there注释:s no way to validate the value to which you want to set
the property. For instance, given the property declaration above, as an
integer data type, the earlier statement

Form1.myProperty = "Fifty"

would generate a type mismatch error.  When you use Get and Let
procedures, on the other hand, you can not only validate potential
property settings and provide meaningful error feedback; but you can
also perform complicated calculations when retrieving or setting these
property values.