try using the css pseudoclass :focus

input[type="button"], input[type="button"]:focus {
  /* your style goes here */
}

edit as for links and onclick events use (you shouldn’t use inline javascript eventhandlers, but for the sake of simplicity i will use them here):

<a href="some/page.php" title="perform some js action" onclick="callFunction(this.href);return false;">watch and learn</a>

with this.href you can even access the target of the link in your function. return false will just prevent browsers from following the link when clicked.

if javascript is disabled the link will work as a normal link and just load some/page.php—if you want your link to be dead when js is disabled use href="#"

You can achieve this using simple css as shown in below example

button {
    overflow: visible;
    width: auto;
}
button.link {
    font-family: "Verdana" sans-serif;
    font-size: 1em;
    text-align: left;
    color: blue;
    background: none;
    margin: 0;
    padding: 0;
    border: none;
    cursor: pointer;
   
    -moz-user-select: text;
 
    /* override all your button styles here if there are any others */
}
button.link span {
    text-decoration: underline;
}
button.link:hover span,
button.link:focus span {
    color: black;
}

<button type="submit" class="link"><span>Button as Link</span></button>

可接受的答案的代码在大多数情况下都有效，但是要获得真正表现得像链接的按钮，您需要更多的代码。在Firefox（Mozilla）上正确设置焦点按钮的样式特别棘手。

以下CSS确保锚点和按钮具有相同的CSS属性，并且在所有常见浏览器上的行为均相同：

button {
  align-items: normal;
  background-color: rgba(0,0,0,0);
  border-color: rgb(0, 0, 238);
  border-style: none;
  box-sizing: content-box;
  color: rgb(0, 0, 238); 
  cursor: pointer;
  display: inline;
  font: inherit;
  height: auto;
  padding: 0;
  perspective-origin: 0 0;
  text-align: start;
  text-decoration: underline;
  transform-origin: 0 0;
  width: auto;
  -moz-appearance: none;
  -webkit-logical-height: 1em; /* Chrome ignores auto, so we have to use this hack to set the correct height  */
  -webkit-logical-width: auto; /* Chrome ignores auto, but here for completeness */
}

/* Mozilla uses a pseudo-element to show focus on buttons, */
/* but anchors are highlighted via the focus pseudo-class. */

@supports (-moz-appearance:none) { /* Mozilla-only */
  button::-moz-focus-inner { /* reset any predefined properties */ 
    border: none;
    padding: 0;
  }
  button:focus { /* add outline to focus pseudo-class */
    outline-style: dotted;
    outline-width: 1px;
  }
}

上面的示例仅修改了button元素以提高可读性，但是也可以轻松地将其扩展为修改input[type="button"], input[type="submit"]和input[type="reset"]元素。如果您只想使某些按钮看起来像锚点，则也可以使用一个类。

See this JSFiddle for a live-demo.

Please also note that this applies the default anchor-styling to buttons (e.g. blue text-color). So if you want to change the text-color or anything else of anchors & buttons, you should do this after the CSS above.

The original code (see snippet) in this answer was completely different and incomplete.

/* Obsolete code! Please use the code of the updated answer. */

input[type="button"], input[type="button"]:focus, input[type="button"]:active,  
button, button:focus, button:active {
	/* Remove all decorations to look like normal text */
	background: none;
	border: none;
	display: inline;
	font: inherit;
	margin: 0;
	padding: 0;
	outline: none;
	outline-offset: 0;
	/* Additional styles to look like a link */
	color: blue;
	cursor: pointer;
	text-decoration: underline;
}
/* Remove extra space inside buttons in Firefox */
input[type="button"]::-moz-focus-inner,
button::-moz-focus-inner {
    border: none;
    padding: 0;
}