Question

我在JavaScript的某些部分有代码，如下所示：

$('table#coa-list').find('tbody').append(
    '<tr align="center">'+
    ' <td class="text-nowrap">'+(element.customer_ID == null? '-' : element.customer_name )+'</td>'+
    ' </td>'+
    ' </tr>'               
)

以上代码代表if(customer_ID == null){echo ...}

如何在条件语句中将另一个条件添加到表达式并与OR运算符（即OR）结合使用？例如，此代码if(customer_ID == null || customer_ID == "0"){echo ...}

Answer 1

如何执行OR语句？例如，此代码if(customer_ID == null || customer_ID == "0"){echo ...} [在三元运算符/语句中]

一种选择是添加logical OR operator（即||），然后添加其他条件：

' <td class="text-nowrap">'+((element.customer_ID == null || element.customer_ID == "0")? '-' : element.customer_name )+'</td>'+

请参阅以下代码段中的演示：

var element = {};

console.log('result of first ternary with OR: ',(element.customer_ID == null || element.customer_ID == "0")? 'null or zero' : element.customer_name );

element.customer_ID = 4;
element.customer_name = 'Bert';

console.log('result of second ternary with OR: ',(element.customer_ID == null || element.customer_ID == "0")? 'null or zero' : element.customer_name );

另一种可能性是用函数调用替换该表达式。首先将逻辑抽象为函数：

function customerIdIsNullOrZero() {
    return element.customer_ID == null || customer_ID == "0";
}

然后使用它，用对该函数的调用替换三元运算符的条件：

' <td class="text-nowrap">'+(customerIdIsNullOrZero()? '-' : element.customer_name )+'</td>'+

var element = {};

function customerIdIsNullOrZero() {
    return element.customer_ID == null || element.customer_ID == "0";
}
console.log('result of first ternary with OR: ',customerIdIsNullOrZero()? 'null or zero' : element.customer_name );

element.customer_ID = 4;
element.customer_name = 'Bert';

console.log('result of second ternary with OR: ',customerIdIsNullOrZero()? 'null or zero' : element.customer_name );

JavaScript中的条件语句和OR操作

1 个答案: