How to write the beginners, bosses solutions, learn from the answer-CodePudding

From the text box input an email, to extract the user name, show the "* * * hello,"

CodePudding user response:

https://blog.csdn.net/l_ppp/article/details/106557211
Use regular expressions to extract, extract the article in my email address and user name code case, you can have a look

CodePudding user response:

 
 
 
 
<meta charset="utf-8" & gt; 
<meta name="viewport" content="width=device - width, initial - scale=1.0" & gt; 
  
 
<body> 
 
 
 
 
<script> 
Let p=document. QuerySelector (' p ') 
Let z=null 
Document. QuerySelector (' input '). The addEventListener (' input, e=& gt; {
Let the dom=e. arget 
ClearTimeout (z) 
If (/^ + @ \ w + \ [a - z0-9], [a-z] {2, 4} $/. The test (dom) value)) {
Let the index=dom. Value. IndexOf (' @ ') 
Let the text=dom. Value. The substring (0, index) 
P.t extContent=${text} ` hello ` 
} else {
Z=setTimeout (()=& gt; {
P.t extContent='you entered is not correct mailbox' 
}, 500) 
} 
}) 
</script>

CodePudding user response:

reference 2 floor to lotus response:

 
 
 
 
<meta charset="utf-8" & gt; 
<meta name="viewport" content="width=device - width, initial - scale=1.0" & gt; 
  
 
<body> 
 
 
 
 
<script> 
Let p=document. QuerySelector (' p ') 
Let z=null 
Document. QuerySelector (' input '). The addEventListener (' input, e=& gt; {
Let the dom=e. arget 
ClearTimeout (z) 
If (/^ + @ \ w + \ [a - z0-9], [a-z] {2, 4} $/. The test (dom) value)) {
Let the index=dom. Value. IndexOf (' @ ') 
Let the text=dom. Value. The substring (0, index) 
P.t extContent=${text} ` hello ` 
} else {
Z=setTimeout (()=& gt; {
P.t extContent='you entered is not correct mailbox' 
}, 500) 
} 
}) 
</script>

Thank you for big help