我有以下代码,使用会话但我在行中有错误:
if (Session["ShoppingCart"] == null)
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错误是cS0103: The name 'Session' does not exist in the current context什么问题?
using System;
using System.Data;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Collections.Generic;
using System.Web.SessionState;
/// <summary>
/// Summary description for ShoppingCart
/// </summary>
public class ShoppingCart
{
List<CartItem> list;
public ShoppingCart()
{
if (Session["ShoppingCart"] == null)
list = new List<CartItem>();
else
list = (List<CartItem>)Session["ShoppingCart"];
}
}
Run Code Online (Sandbox Code Playgroud) 我尝试了以下代码将转换LinearLayout为图像:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
LinearLayout lyt = (LinearLayout) findViewById(R.id.lyt);
lyt.setDrawingCacheEnabled(true);
lyt.buildDrawingCache(true);
Bitmap b = Bitmap.createBitmap(lyt.getDrawingCache());
ImageView img = (ImageView) findViewById(R.id.imageView1);
img.setImageBitmap(b);
}
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但我NullPointerException进去了:
Bitmap b = Bitmap.createBitmap(lyt.getDrawingCache());
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布局XML是:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:id="@+id/lyt"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 1" />
<Button
android:id="@+id/button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 2" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 3" />
</LinearLayout>
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
</LinearLayout>
Run Code Online (Sandbox Code Playgroud) 如何迭代items在给定行中的所有内容DataTable.我有以下代码来迭代所有行,我想要另一个For循环迭代给定行中的所有单元格?
For Each row As DataRow In dt.Rows
Next row
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我可以访问每一行,但我想访问该行的每一列,因为我不知道列的名称和计数,..
我.android在Ubuntu 哪里可以找到我想要使用的debug.keystore?
我要对齐的DIV c中的底部DIV b不DIV a
<div id="a">
<div id="b">
<div id="c">
Div c
</div>
</div>
</div>
Run Code Online (Sandbox Code Playgroud) 我想使用自定义功能的自定义应用animationAndroid view(按钮)上的翻译interpolator:
public static float easeOut(float t,float b , float c, float d) {
if ((t/=d) < (1/2.75f)) {
return c*(7.5625f*t*t) + b;
} else if (t < (2/2.75f)) {
return c*(7.5625f*(t-=(1.5f/2.75f))*t + .75f) + b;
} else if (t < (2.5/2.75)) {
return c*(7.5625f*(t-=(2.25f/2.75f))*t + .9375f) + b;
} else {
return c*(7.5625f*(t-=(2.625f/2.75f))*t + .984375f) + b;
}
}
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我有一个使用自定义插补器的示例,如下所示:
插值器是:
public class HesitateInterpolator implements Interpolator {
public HesitateInterpolator() {
}
public float getInterpolation(float …Run Code Online (Sandbox Code Playgroud)