【正文】 Visual Basic statements ? Carry out actions ? Written inside procedures ? May have arguments ?Multiple arguments are separated with mas ?Some arguments are optional Private Sub ShowMsgBox() Beep MsgBox ESRI End Sub Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 226 ? InputBox to get information ? MsgBox to report a message ? Combine (concatenate) strings with amp。 … ? Get the Date or Time … Some mon Visual Basic functions MsgBox ArcMap is Great! MsgBox The date is amp。 Date MsgBox The time is amp。 Time MsgBox The date and time is amp。 Now InputBox Enter the new Landuse Code: Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 228 過程類型 Procedure types ? 事件過程 Event procedures ?有一個相關(guān)聯(lián)的對象 Have an associated object (., control) ?當(dāng)相應(yīng)的事件發(fā)生時運行代碼 Code runs when the corresponding event occurs (., click) ? 子程序（ SUB） 和功能（ Functions ）過程 ?沒有相關(guān)聯(lián)的對象 No associated object ?必須被調(diào)用才能運行 Must be called ?功能過程返回一個值 Functions return a value Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 229 Running an event procedure ? 控件（ Controls） 有預(yù)先定義的一組事件 ?你可以選擇相應(yīng)的事件去添加代碼 ? 當(dāng)一個事件被激發(fā)，相關(guān)的代碼將被運行 Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 230 ? Choose a control in the Object box Object box Procedure box ? Choose an event in the Procedure box 自動添加事件過程的封裝行 在模塊中瀏覽事件過程 A MsgBox Hi! Write code to run when UIButtonControl1 is clicked Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 231 The ThisDocument module ? 與一個文檔相關(guān)的代碼可以包含在： ?Normal template ?Current map document (mxd) ?Base template (optional) ? 可以在任何一個層次中客戶化 Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 232 Creating a new module ? Module (標(biāo)準(zhǔn)模塊 ): 包含常量、子程序、功能過程等 ? Class module: 包含一個類的定義 ? UserForm: 包含代碼、窗體的布局等 Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 233 Creating a new sub or function procedure (macro) ? Scope: Public or Private ? Sub or Function: Functions return a value ? Parameters: List all required inputs ? Return Type: Type of data returned (functions only) Return Type Name Parameter List Scope Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 235 Defining procedure scope ? Public:可以在任何模塊中調(diào)用該過程 ? Private: 只能被同一個模塊中其它過程調(diào)用 Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 236 Running a sub（） or function（） procedure ? 沒有事件去激活這些過程的運行 ? 必須調(diào)用這些過程 ?通過宏菜單運行：從界面進行調(diào)用 ?調(diào)用過程的申明 : 從代碼中進行調(diào)用 Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 237 Adding a macro to a toolbar ? Macros category of the Customize dialog ? Macro bees a button on the toolbar ?Edit the control’s properties Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 238 Getting help ? F1 key for contextsensitive help ? Visual Basic Help Topics ? ArcObjects Developer Help ? ESRI Web site Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 239 Exercise 2 overview ? Explore the Visual Basic Editor ? Navigate event procedures ? Add a new code module ? Run procedures ? Export code to a file on disk Copyright 169。 2020, 2020 ESRI. All rights reserved. Introduction to Programming ArcObjects with VBA Visual Basic code: How, where, and when?（ II） Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 241 在 VBA中怎么編寫代碼 ? How? ?Objectoriented programming ?Visual Basic syntax ?Application and ThisDocument variables ? Where? ?Creating forms and controls ? When? ?Document, control, and form events Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 242 Objectoriented programming ? 對象是 … ?Visual Basic: Forms, text boxes, mand buttons, … ?ArcObjects: Maps, layers, symbols, tables, … ? 操作對象 ?Properties: Characteristics of an object ?Methods: Things an object knows how to do ?Events: Actions that an object can respond to Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 243 Map Car Property 地圖單位 馬力 Method 添加圖層 加速 Event 選擇集改變 踩剎車 Example: Objectoriented terms Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 244 How: Visual Basic syntax ? Get the value of a property with ? Assign a value to a property with = value ? Call methods with arg1, .., argN ? ArcObject events will be covered in Lesson 15 MsgBox The map name is amp。 = CityLayer CityLayer, KahembaPoint Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 246 Preset ArcObjects variables ? 在 VBA環(huán)境下的 ArcObjects變量的全局變量 ?Application ?ThisDocument ? 作為編程的一個起始點 ? More about variables in the next lesson MsgBox You are currently working in amp。 MsgBox The current map is amp。 Object Property Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 248 ? 列出可用的屬性和方法 ? 當(dāng)一個對象名被輸入的時候自動顯示 ?如果沒有顯示出自動完成的列表，則表示該對象沒有被認證 ? 使用 Tab, Enter, or Space 去選擇所需的屬性和方法 VBA的自動代碼完成功能 Press Tab, Enter, or Space Introduction to Programming ArcObjects with VBA Copyright 169。 2020, 2020 ESRI. All rights reserved. 250 Where: Controls, documents, and forms ? Create UIControls ? Store macros with the docu