1.kotlin基础:数据类型

1.Boolean

val bl: Boolean = true

2.基本类型

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val along: Long = 123
val aInt: Int = 123

val aFloat: Float = 123.0F
val aDouble: Double = 123.0

//不可隐式转换  必须显示转换
val aLong: Long = aInt.toLong()

3.字符和字符串

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val aChar： Char = ‘a’
val cChar: Char = \u000f'  //Unicode

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4.数组

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5.类和对象

1>.注意：可以在类名后面直接写构造方法的参数

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2>.智能类型转换（Parent is Child）

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6.包 package 和 区间

1>包

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2>.区间

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