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I have a page with a textbox where a user is supposed to enter a 24 character (letters and numbers, case insensitive) registration code. 我有一个带有文本框的页面，用户应在其中输入24个字符（字母和数字，不区分大小写）的注册码。 I used maxlength to limit the user to entering 24 characters. 我使用maxlength将用户限制为输入24个字符。

The registration codes are typically given as groups of characters separated by dashes, but I would like for the user to enter the codes without the dashes. 注册代码通常以破折号分隔的字符组形式给出，但是我希望用户输入不带破折号的代码。

How can I write my JavaScript code without jQuery to check that a given string that the user inputs does not contain dashes, or better yet, only contains alphanumeric characters? 如何在没有jQuery的情况下编写我的JavaScript代码，以检查用户输入的给定字符串不包含破折号，或者更好的是，仅包含字母数字字符？

#1楼

参考：

#2楼

检查字符串（单词/句子...）是否包含特定的单词/字符

if ( "write something here".indexOf("write som") > -1 )  { alert( "found it" );  }

#3楼

Working perfectly.This exmple will help alot. 完美的工作。这个例子会很有帮助。

    
My form 
    
   
        
    
            UserName :         
        
    
            Password :         
        
    
                    
        
        
   

#4楼

Try this: 尝试这个：

if ('Hello, World!'.indexOf('orl') !== -1)    alert("The string 'Hello World' contains the substring 'orl'!");else    alert("The string 'Hello World' does not contain the substring 'orl'!");

Here is an example: 这是一个示例： :

#5楼

You're all thinking too hard. 你们都在想 Just use a simple Regular Expression, it's your best friend. 只需使用一个简单的正则表达式，它就是您最好的朋友。

var string1 = "Hi Stack Overflow. I like to eat pizza."var string2 = "Damn, I fail."var regex = /(pizza)/g // Insert whatever phrase or character you want to findstring1.test(regex); // => truestring2.test(regex); // => false

#6楼

var inputString = "this is home"; var findme = "home"; if ( inputString.indexOf(findme) > -1 ) { alert( "found it" ); } else { alert( "not found" ); }

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