我正在尝试从我的 SQLite 数据库中检索一些信息,用于 Android 应用程序的登录页面。从数据库中检索的代码是:
login.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
SQLiteDatabase db = SQLiteDatabase.openDatabase("/data/data/com.example.androidproject/databases/myDB", null, 0);
// Check Login
String username = usernamelogin.getText().toString();
String password = loginpassword.getText().toString();
Cursor c = db.rawQuery("SELECT name, password FROM User WHERE name='?' AND password='?'", new String[] {username, password});
if(c.moveToFirst()) {
Intent intent=new Intent(Login.this, MainActivity.class);
startActivity(intent);
} else {
Toast.makeText(getApplicationContext(), "Invalid", Toast.LENGTH_LONG).show();
}
c.close();
db.close();
}
});
但我不断收到此错误:
03-12 20:38:40.216: E/AndroidRuntime(691): FATAL EXCEPTION: main
03-12 20:38:40.216: E/AndroidRuntime(691): java.lang.IllegalArgumentException: Cannot bind argument at index 2 because the index is out of range. The statement has 0 parameters.
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteProgram.bind(SQLiteProgram.java:212)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteProgram.bindString(SQLiteProgram.java:166)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteProgram.bindAllArgsAsStrings(SQLiteProgram.java:200)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:47)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1253)
03-12 20:38:40.216: E/AndroidRuntime(691): at com.example.androiddiet.Login$2.onClick(Login.java:61)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.view.View.performClick(View.java:4084)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.view.View$PerformClick.run(View.java:16966)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.os.Handler.handleCallback(Handler.java:615)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.os.Handler.dispatchMessage(Handler.java:92)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.os.Looper.loop(Looper.java:137)
03-12 20:38:40.216: E/AndroidRuntime(691): at android.app.ActivityThread.main(ActivityThread.java:4745)
03-12 20:38:40.216: E/AndroidRuntime(691): at java.lang.reflect.Method.invokeNative(Native Method)
03-12 20:38:40.216: E/AndroidRuntime(691): at java.lang.reflect.Method.invoke(Method.java:511)
03-12 20:38:40.216: E/AndroidRuntime(691): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
03-12 20:38:40.216: E/AndroidRuntime(691): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
03-12 20:38:40.216: E/AndroidRuntime(691): at dalvik.system.NativeStart.main(Native Method)
最佳答案
不要用引号将替换字符括起来:
WHERE name=? AND password=?
使用
name='?'
将尝试将 name
与文字问号进行比较...关于java - 参数化查询抛出 IllegalArgumentException : Cannot bind argument,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/15371734/