javascript passing text input to a onclick handler

问题:

Lets say I have a form as below. How do I pass the value in the textbox named "configname" to the onclick function handler??

<form id="loadconfigform">
        Config Name: <input type="text" name="configname" />
        <input type="button" value="Submit" onclick="onLoadConfigPress(configname)" />
    </form>

回答1:

Give an id to input field:

<input type="text" id="configname" name="configname" />

Now modify click handler as follows:

<input type="button" value="Submit" 
  onclick="onLoadConfigPress(document.getElementById('configname').value)" />

Or if you have only one form on that page, you could also use forms array:

<input type="button" value="Submit" 
  onclick="onLoadConfigPress(document.forms[0].configname.value)" />

回答2:

<form id="loadconfigform">
   Config Name: <input type="text" id="configname" name="configname" />
   <input type="button" value="Submit"
     onclick="onLoadConfigPress(document.getElementById('configname').value);" />
</form>

回答3:

<form id="loadconfigform">
        Config Name: <input type="text" name="configname" />
        <input type="button" value="Submit" onclick="onLoadConfigPress(document.getElementsByName('configname')[0].value)" />
    </form>

Simply call it using its name. I'd recommend using ID though.

This won't work if you have other elements with the same name, so do use ID like the other answers have suggested.