一、代码示例

function fu(s) {
	str = '';
	ste = '';
	console.log(s);
	let Things = s;
	for (let i = 0; i < Things.length; i++) {
		if (Things[i].pid == kk) {
			console.log(Things[i].pid);
			ste += `
		<div class="commodity_nei">
			<div class="zxc_pic">
				<div class="wan">
					<img src="https://wwz.jingyi.icu/${Things[i].img}" alt="">
				</div>
				<div class="bao">
					<div class="fenn">
						<p>${Things[i].nickname}</p>
					</div>
					<div class="fen">
						<p>${Things[i].create_time}</p>
		
					</div>
				</div>
		
			</div>
		</div>
		`
		} else {
			str = `
		<div class="null">
		暂无数据
		</div>
		`
		}
		
		
	}
		$('.null').html(str)
	$('.commodity_nei').html(ste)
	
}

二、效果图

三、解决方式

在循环里添加一个状态去解决此类问题

代码

function fu(s) {
	str = '';
	ste = '';
	let nums = 0;
	console.log(s);
	let Things = s;
	for (let i = 0; i < Things.length; i++) {
		if (Things[i].pid == kk) {
			console.log(Things[i].pid);
			nums++
			ste += `
		<div class="commodity_nei">
			<div class="zxc_pic">
				<div class="wan">
					<img src="https://wwz.jingyi.icu/${Things[i].img}" alt="">
				</div>
				<div class="bao">
					<div class="fenn">
						<p>${Things[i].nickname}</p>
					</div>
					<div class="fen">
						<p>${Things[i].create_time}</p>
		
					</div>
				</div>
		
			</div>
		</div>
		`
		} else {
			str = `
		<div class="null">
		暂无数据
		</div>
		`
		}
	}
	console.log(nums);
	if(nums>0){
		$('.commodity_nei').html(ste)
	}else{
		$('.null').html(str)
	}
}

四、效果图

总结在循环里写判断当条件满足时都会执行，我们需要在循环进行判断输出；

希望可以帮助大家解决问题