Javascript 如何根据传递给函数的值从javascript中的数据库中获取数据
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11027982/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to get data from database in javascript based on the value passed to the function
提问by user25
In my web application, I want to retrieve data from database based on the value that is passed to the function. I wrote the query as follows.
在我的 Web 应用程序中，我想根据传递给函数的值从数据库中检索数据。我按如下方式编写了查询。
<script>
//Functions to open database and to create, insert data into tables
getSelectedRow = function(val)
{
db.transaction(function(transaction) {
transaction.executeSql('SELECT * FROM Employ where number = parseInt(val);',[], selectedRowValues, errorHandler);
});
};
selectedRowValues = function(transaction,results)
{
for(var i = 0; i < results.rows.length; i++)
{
var row = results.rows.item(i);
alert(row['number']);
alert(row['name']);
}
};
</script>
In body tag,
在身体标签中，
<body>
---
<a href = "#" onClick = "javascript:getSelectedRow('1')>getValues</a>
I got the problem while retrieving data from database, i.e., at SELECT query. It doesn't accept the value parseInt(val), if I give the condition as 'name = 1' it simply accepts the condition and give the result, but it doesn't accept 'name = parseInt(val)' and throws error as 'no such column: val code: 1' Please tell me how to pass value in 'val'.. Thanks in Advance..
我在从数据库中检索数据时遇到了问题，即在 SELECT 查询中。它不接受值 parseInt(val)，如果我将条件指定为 'name = 1' 它只是接受条件并给出结果，但它不接受 'name = parseInt(val)' 并抛出错误如“没有这样的列：val 代码：1”请告诉我如何在“val”中传递值.. 提前致谢..
采纳答案by Esailija
'SELECT * FROM Employ where number = ' + parseInt(val, 10) + ';'
For example, if valis "10"then this will end up building the string:
例如，如果val是"10"那么这将最终构建字符串：
"SELECT * FROM Employ where number = 10;"
回答by Ankit
The error is coming as your query is getting formed as
当您的查询形成为
SELECT * FROM Employ where number = parseInt(val);
I dont know which DB you are using but no DB will understand parseInt.
我不知道您使用的是哪个数据库，但没有数据库会理解parseInt。
What you can do is use a variable say temp and store the value of parseInt(val)in temp variable and make the query as
您可以做的是使用一个变量说 temp 并将其值存储parseInt(val)在 temp 变量中并使查询为
SELECT * FROM Employ where number = temp;
回答by DThought
Try the following:
请尝试以下操作：
<script>
//Functions to open database and to create, insert data into tables
getSelectedRow = function(val)
{
db.transaction(function(transaction) {
transaction.executeSql('SELECT * FROM Employ where number = ?;',[parseInt(val)], selectedRowValues, errorHandler);
});
};
selectedRowValues = function(transaction,results)
{
for(var i = 0; i < results.rows.length; i++)
{
var row = results.rows.item(i);
alert(row['number']);
alert(row['name']);
}
};
</script>
You don't have access to javascript variable names in SQL, you must pass the values to the Database.
您无权访问 SQL 中的 javascript 变量名称，您必须将值传递给数据库。
