javascript 提交前验证表单 -JSP
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Validate form before submitting -JSP
提问by Shiju K Babu
in my JSP page i created a form,
在我的 JSP 页面中，我创建了一个表单，
<form class="form-horizontal" id="genericDatabaseLoad" name="genericDatabaseLoad"
action="genericDatabaseLoad" method="post" onsubmit="validateDBFom()">
<fieldset>
<input type="radio" name="connectionType" value="jdbcConnection"> <b><s:text name="global.genericdb_jdbc_connection" /></b>
<div class="dbConnection" id="jdbcConnection" style="display: none; position: relative; left: 30px;">
<div class="control-group">
<label class="control-label input-label" for="hostname"><s:text name="global.genericdb_hostname" /> :
<span class="requiredField"> * </span>
</label>
<div class="controls">
<input type="text" class="inputstyle" id="dbHostname" name="hostname" placeholder="<s:text name="global.genericdb_hostname" />" required="required" />
</div>
</div>
<div class="control-group">
<label class="control-label input-label" for="port"><s:text name="global.genericdb_port" /> :
<span class="requiredField"> * </span>
</label>
<div class="controls">
<input type="text" class="inputstyle" name="port" placeholder="<s:text name="global.genericdb_port" />" required="required" />
</div>
</div>
<div class="control-group">
<label class="control-label input-label" for="dbname"><s:text name="global.genericdb_databasename" />:</label>
<div class="controls">
<input type="text" class="inputstyle" name="dbname" placeholder="<s:text name="global.genericdb_databasename" />"
required="required" />
</div>
</div>
<div class="control-group">
<label class="control-label input-label" for="username"><s:text name="global.genericdb_username" /> :
<span class="requiredField"> * </span>
</label>
<div class="controls">
<input type="text" class="inputstyle" name="username" placeholder="<s:text name="global.genericdb_username" />" required="required" />
<label class="input-tip"><s:text name="global.genericdb_username_info" /></label>
</div>
</div>
<div class="control-group">
<label class="control-label input-label" for="password"><s:text name="global.genericdb_password" />:</label>
<div class="controls">
<input type="password" class="inputstyle" name="password" placeholder="<s:text name="global.genericdb_password" />" />
<label class="input-tip"><s:text name="global.genericdb_password_info" /></label>
</div>
</div>
</div>
<input type="radio" name="connectionType" value="jndiConnection"> <b><s:text name="global.genericdb_jndi_connection" /></b>
<div class="dbConnection" id="jndiConnection" style="display: none; position: relative; left: 30px;">
<div class="control-group">
<label class="control-label input-label" for="jndidbType"><s:text name="global.genericdb_jndi_databse" />:</label>
<div class="controls">
<select id="jndidbType" class="inputstyle" name="jndidbType">
<option value="oracle">Oracle</option>
<option value="sybase">Sybase</option>
<option value="mssql">MS SQL</option>
<option value="mysql">MySQL</option>
<option value="other">Other</option>
</select>
</div>
</div>
<div class="control-group">
<label class="control-label input-label" for="jndiConnectionString"><s:text name="global.genericdb_jndi_connection_string" />:</label>
<div class="controls">
<input type="text" class="inputstyle" name="jndiConnectionString"
placeholder="<s:text name="global.genericdb_jndi_connection_string" />" />
</div>
</div>
</div>
<div class="control-group" style="position: relative; top: 15px; left: 30px;">
<label class="control-label input-label" for="query"><s:text name="global.genericdb_query" /> :
<span class="requiredField"> * </span>
</label>
<div class="controls">
<textarea name="query" rows="4" placeholder="<s:text name="global.genericdb_query" />"
required="required" ></textarea>
<label class="input-tip"><s:text name="global.genericdb_query_info" /></label>
</div>
</div>
</fieldset>
</form>
As you can see there is no Submit button inside the formI am adding submit button outside of form.
如您所见，表单内没有提交按钮，我在表单外添加提交按钮。
<button type="submit" id="submitbtn" class="btn btn-primary inputstyle" onclick="submitForm();">SUBMIT</button>
So when I click on submit button, it will submit the form to struts action. JQuery is
所以当我点击提交按钮时，它会将表单提交给 struts 操作。JQuery 是
JQuery is
JQuery 是
<script>
function submitForm() {
var $submitform=$('#formId').val();
$('#'+$submitform).submit(); // $submitform is the id of the form.
}
</script>
Jquery to validate the form is
用于验证表单的 Jquery 是
function validateDBFom()
{
var selectedVal = "";
var selected = $("input[type='radio'][name='connectionType']:checked");
if (selected.length > 0)
{
selectedValue = selected.val();
if(selectedValue=="jdbcConnection")
{
var $dbHostname=$("#dbHostname").val();
alert($dbHostname);
if($dbHostname==""||$dbHostname==null)
{
alert("Please fill host name");
return false;
}
}
}
else
{
alert("Please Select Connection Type.");
return false;
}
}
When I click on the submit button without selecting any radio button, it is displaying the correct message. That is, form validation is happening correctly. But if it return false also, the form is still submitting to action. What should I do to stay in the page without submitting if the validation function returns false?
当我点击提交按钮而不选择任何单选按钮时，它会显示正确的消息。也就是说，表单验证正确发生。但如果它也返回 false，则表单仍在提交操作。如果验证函数返回false，我应该怎么做才能留在页面而不提交？
回答by rahul maindargi
You code is correct except this line
除了这一行，你的代码是正确的
<form class="form-horizontal" id="genericDatabaseLoad" name="genericDatabaseLoad"
action="genericDatabaseLoad" method="post" onsubmit="validateDBFom()">
you should use
你应该使用
<form class="form-horizontal" id="genericDatabaseLoad" name="genericDatabaseLoad"
action="genericDatabaseLoad" method="post" onsubmit="return validateDBFom();">
Notice changes in onsubmit
通知更改 onsubmit
