我想知道为什么+=有效但=+无效.假设我有这样的代码:
string strOne = "World!";
strOne =+ "Hello ";//strOne = "Hello " + strOne; not valid
//Error: Operator '+' cannot be applied to operand of type 'string'
//Intended Output: Hello World!
string strTwo = "Hello ";
strTwo += "World!";//strTwo = strTwo + "World!"; valid
//Output: Hello World!
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我也不确定是否strOne =+ "Hello ";相同strOne = "Hello " + strOne;.是否有任何关于为什么=+无效或无法在语法上正确的规则?
简单的答案是否定的,没有=+运营商.你必须这样做
strTwo = "Hello " + strTwo;
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不存在的部分原因可能是+数字类型的有效一元运算符.
var intValue = +2;
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