jquery radio的操作:
<code class="language-html"><input type="radio" name="rd" checked id="rd1" value="rd1"> <input type="radio" name="rd" id="rd2" value="rd2"> <input type="radio" name="rd" id="rd3" value="rd3"></code>
1.获取选中值,三种方法都可以:
<code class="language-javascript">$('input:radio:checked').val(); $("input[type='radio']:checked").val(); $("input[name='rd']:checked").val(); </code>
2.设置第一个Radio为选中值:
<code class="language-javascript">$('input:radio:first').attr('checked', 'checked'); 或者 $('input:radio:first').attr('checked', 'true');</code>
注: attr("checked",'checked')= attr("checked", 'true')= attr("checked", true)
3.设置最后一个Radio为选中值:
<code class="language-javascript">$('input:radio:last').attr('checked', 'checked'); 或者 $('input:radio:last').attr('checked', 'true'); </code>
4.根据索引值设置任意一个radio为选中值:
<code class="language-javascript">$('input:radio').eq(索引值).attr('checked', 'true');索引值=0,1,2.... 或者 $('input:radio').slice(1,2).attr('checked', 'true'); </code>
5.根据Value值设置Radio为选中值
<code class="language-javascript">$("input:radio[value='rd2']").attr('checked','true'); 或者 $("input[value='rd2']").attr('checked','true'); </code>
6.删除Value值为rd2的Radio
<code class="language-javascript">$("input:radio[value='rd2']").remove(); </code>
7.删除第几个Radio
<code class="language-javascript">$("input:radio").eq(索引值).remove();索引值=0,1,2.... 如删除第3个Radio:$("input:radio").eq(2).remove(); </code>
8.遍历Radio
<code class="language-javascript">$('input:radio').each(function(index,domEle){ //写入代码 }); </code>
jquery select的操作
<code class="language-html"><select id="sel"> <option value="1" selected>a</option> <option value="2">b</option> <option value="3">c</option> <option value="4">d</option> <option value="5">e</option> </select></code>
1. 获取选中项:
获取选中项的Value值:
<code class="language-javascript">$('select#sel option:selected').val(); 或者 $('select#sel').find('option:selected').val(); </code>
获取选中项的Text值:
<code class="language-javascript">$('select#seloption:selected').text(); 或者 $('select#sel').find('option:selected').text();</code>
2. 获取当前选中项的索引值:
<code class="language-javascript">$('select#sel').get(0).selectedIndex; </code>
3. 获取当前option的最大索引值:
<code class="language-javascript">$('select#sel option:last').attr("index") </code>
4. 获取DropdownList的长度:
<code class="language-javascript">$('select#sel')[0].options.length; 或者 $('select#sel').get(0).options.length; </code>
5. 设置第一个option为选中值:
<code class="language-javascript">$('select#sel option:first').attr('selected','true') 或者 $('select#sel')[0].selectedIndex = 0; </code>
6. 设置最后一个option为选中值:
<code class="language-javascript">$('select#sel option:last).attr('selected','true') </code>
7. 根据索引值设置任意一个option为选中值:
<code class="language-javascript">$('select#sel')[0].selectedIndex =索引值;索引值=0,1,2.... </code>
8. 设置Value=4 的option为选中值:
<code class="language-javascript">$('select#sel').attr('value','4'); 或者 $("select#sel option[value='4']").attr('selected', 'true'); </code>
9. 删除Value=3的option:
<code class="language-javascript">$("select#sel option[value='3']").remove(); </code>
10.删除第几个option:
<code class="language-javascript">$(" select#sel option ").eq(索引值).remove();索引值=0,1,2.... 如删除第3个Radio: $(" select#sel option ").eq(2).remove(); </code>
11.删除第一个option:
<code class="language-javascript">$(" select#sel option ").eq(0).remove(); 或者 $("select#sel option:first").remove();</code>
12. 删除最后一个option:
<code class="language-javascript">$("select#sel option:last").remove(); </code>
13. 删除dropdownlist:
<code class="language-javascript">$("select#sel").remove(); </code>
14.在select后面添加一个option:
<code class="language-javascript">$("select#sel").append("<option value="6">f</option>");</code>
15. 在select前面添加一个option:
<code class="language-javascript">$("select#sel").prepend("<option value="0">0</option>"); </code>
16. 遍历option:
<code class="language-javascript">$(' select#sel option ').each(function (index, domEle) { //写入代码 }); </code>
jquery checkbox的操作
<code class="language-html"><input type="checkbox" name="ck1" checked id="ck1" value="1"> <input type="checkbox" name="ck2" id="ck2" value="2"> <input type="checkbox" name="ck3" id="ck3" value="3"> <input type="checkbox" name="ck4" id="ck4" value="4"></code>
1. 获取单个checkbox选中项(三种写法):
<code class="language-javascript">$("input:checkbox:checked").val() 或者 $("input:[type='checkbox']:checked").val(); 或者 $("input:[name='ck']:checked").val(); </code>
2. 获取多个checkbox选中项:
<code class="language-javascript">$('input:checkbox').each(function() { if ($(this).attr('checked') ==true) { alert($(this).val()); } }); </code>
3. 设置第一个checkbox 为选中值:
<code class="language-javascript">$('input:checkbox:first').attr("checked",'checked'); 或者 $('input:checkbox').eq(0).attr("checked",'true'); </code>
4. 设置最后一个checkbox为选中值:
<code class="language-javascript">$('input:radio:last').attr('checked', 'checked'); 或者 $('input:radio:last').attr('checked', 'true'); </code>
5. 根据索引值设置任意一个checkbox为选中值:
<code class="language-javascript">$('input:checkbox).eq(索引值).attr('checked', 'true');索引值=0,1,2.... 或者 $('input:radio').slice(1,2).attr('checked', 'true');</code>
6. 选中多个checkbox:
同时选中第1个和第2个的checkbox:
<code class="language-javascript">$('input:radio').slice(0,2).attr('checked','true'); </code>
7. 根据Value值设置checkbox为选中值:
<code class="language-javascript">$("input:checkbox[value='1']").attr('checked','true'); </code>
8. 删除Value=1的checkbox:
<code class="language-javascript">$("input:checkbox[value='1']").remove(); </code>
9. 删除第几个checkbox:
<code class="language-javascript">$("input:checkbox").eq(索引值).remove();索引值=0,1,2.... 如删除第3个checkbox: $("input:checkbox").eq(2).remove(); </code>
10.遍历checkbox:
<code class="language-javascript">$('input:checkbox').each(function (index, domEle) { //写入代码 }); </code>
11.全部选中
<code class="language-javascript">$('input:checkbox').each(function() { $(this).attr('checked', true); }); </code>
12.全部取消选择
<code class="language-javascript">$('input:checkbox').each(function () { $(this).attr('checked',false); });</code>

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