4.16. Lua if nested statement

发布时间 : 2025-10-25 13:34:10 UTC      

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4.16.1. If…else statement #

Lua if statement allows nesting, which means that you can use a if or else if statement to insert other if or else if statement.

4.16.2. The syntax format of Lua if nested statements is as follows: #

if(Boolean expression 1) then --[Execute the statement block when Boolean expression 1 is true--] if(Boolean expression 2) then --[Execute the statement block when Boolean expression 2 is true--] end end 

You can nest in the same way else statement.

4.16.3. Example #

The following example is used to determine a variable a and b Value:

Example #

--[Define variables--] a = 100; b = 200; --[Check Condition--] if( a == 100 ) then --[Perform the following if condition judgment when the if condition is true--] if( b == 200 ) then --[Execute the statement block when the if condition is true--] print("The value of a is 100, and the value of b is 200" ); end end print("The value of a is:", a ); print("The value of b is:", b ); 

The execution result of the above code is as follows:

The value of a is 100, and the value of b is 200 The value of a is: 100 The value of b is: 200 
《地理信息系统原理、技术与方法》  97

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