在圖像src中添加另一個變量？

Question

<img src="blank.png" id="image" alt="just nothing"> 

<script type="text/javascript"> 
document.getElementById('image').src = '"'+ img +'"'; 
var img = new Image(); 
img.src = "https://pbs.twimg.com/profile_images/696014803844927488/8aLamHjS.jpg"; 
</script> 

這不起作用。我很困惑。

Answer 1

您正在訪問的變量image聲明之前，你的代碼應該是這樣的：

var img = new Image(); 
img.src = "https://pbs.twimg.com/profile_images/696014803844927488/8aLamHjS.jpg"; 

document.getElementById('image').src = img.src; 

看看這個fiddle

Answer 2

你的代碼改成這樣

var img = "https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png"; 
 
document.getElementById('image').src = img ;

<img src="blank.png" id="image" alt="just nothing">

您可以直接申請在src

document.getElementById('image').src = "https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png"; 
 

<img src="blank.png" id="image" alt="just nothing">