⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 class_book_begin044.htm

📁 vb实例,很好很好用的哦,处学者的天堂这是第四部分
💻 HTM
字号:
🔍 
<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<style>
.redLink{ color:red;}
.blueLink{color:blue;}
A{font-size:12pt;text-decoration:none;}
P{font:12pt;line-height:22px;}
h2{font-size:30px;text-align:center;color:rgb(0,144,144);letter-spacing:.5em;font-weight:bold}
.whiteB{color:black;background-color:white;}
.blueB{color:yellow;background-color:blue;}
.blackB{color:white;background-color:black;}
</style>
<title>第四章：按钮</title>
</head>
<script langue="javascript">
<!--
var source;
var flagDU="Up";
var oldClass="";
function ChangeColor(){
 source=window.event.srcElement;
 if (source.className=="redLink"){
  source.className="blueLink";
 }
 else{
  source.className="redLink";
 }
}

function moveChangeBack(){
 source=window.event.srcElement;
 if (source.className==oldClass){oldClass=source.className; 
    if (flagDU=="Up"){
      if (source.className="whiteB"){
         source.className="blueB";
      }else{
      source.className="whiteB";
      }
   }else{source.className="blackB";
   }
 }else{//oldClass=source.className; 
   if (source.className=="whiteB"){
     source.className="blueB";
   }else{
     source.className="whiteB";
   }
 } 
}

function clickChangeBack(){
  index01.className="whiteB"
  index02.className="whiteB"
 source=window.event.srcElement;
 source.className="blackB";
  flagDU="Down";
oldClass=source.className; 
}

function returnValue(){
 index01.className="whiteB";
 index02.className="whiteB";
 flagDU="Up";
}

function getAppVersion()
                {
                appname= navigator.appName;
                appversion = navigator.appVersion;
                majorver = appversion.substring(0, 1);
                if ( (appname == "Netscape") && ( majorver >= 3 ) ) return 1;
                if ( (appname == "Microsoft Internet Explorer") && (majorver>= 4) ) return 1;
        return 0;
                }

function switchGraphic(num, imgname) {
  if (getAppVersion()) {
 document[imgname].src = img[num].src;
 }
}//-->
</script>


<body>
<script language="javascript">
<!--
imgsrc = new Array();
imgsrc[0] = "images/dot_blank.gif";
imgsrc[1] = "images/dot_filled.gif";
if (getAppVersion())
                {
        img = new Array();
        for (i = 0; i < imgsrc.length; i++)
                                {
                img[i] = new Image();
                img[i].src = imgsrc[i];
                        }
                }
//-->
</script>
<div align="center"><center>

<table border="0" cellpadding="8" cellspacing="0" width="100%">
  <tr>
    <td width="24%" valign="top"><h2><img src="../images/class_img.gif" WIDTH="160" HEIGHT="51"></h2>
    <hr size="4" color="#FF0000" width="75%">
    <p align="center"><img src="../images/menu_bar_jc_d.gif" WIDTH="150" HEIGHT="35"><img src="../images/dot_blank.gif" name="b1" WIDTH="10" HEIGHT="35"><br>
    <a href="../class_api.htm" onMouseOver="switchGraphic('1','b2')" onMouseOut="switchGraphic('0','b2')"><img src="../images/menu_bar_api.gif" border="0" WIDTH="150" HEIGHT="35"></a><img src="../images/dot_blank.gif" name="b2" WIDTH="10" HEIGHT="35"><br>
    <span align="center"><a href="../class_wz.htm" onMouseOver="switchGraphic('1','b5')" onMouseOut="switchGraphic('0','b5')"><img src="../images/menu_bar_wz.gif" border="0" WIDTH="150" HEIGHT="35"></a><img src="../images/dot_blank.gif" name="b5" WIDTH="10" HEIGHT="35"></span><br>
    <a href="../class_tip.htm" onMouseOver="switchGraphic('1','b3')" onMouseOut="switchGraphic('0','b3')"><img src="../images/menu_bar_tip.gif" border="0" WIDTH="150" HEIGHT="35"></a><img src="../images/dot_blank.gif" name="b3" WIDTH="10" HEIGHT="35"><br>
    <a href="../class_fqa.htm" onMouseOver="switchGraphic('1','b4')" onMouseOut="switchGraphic('0','b4')"><img src="../images/menu_bar_end_fqa.gif" border="0" WIDTH="150" HEIGHT="35"></a><img src="../images/dot_blank.gif" name="b4" WIDTH="10" HEIGHT="35"></p>
    <p align="center"><a href="../context.htm"><img src="../images/logo_return.jpg" border="0" WIDTH="70" HEIGHT="260"></a></td>
    <td width="76%" valign="top" align="center"><div align="center"><center><table border="0" cellpadding="8" cellspacing="0" width="27%" style="background-color: rgb(0,128,128)">
      <tr>
        <td width="100%" valign="top" align="center"><a name="top"><font size="5" color="#C0C0C0"><strong>VB入门教程</strong></font></a></td>
      </tr>
    </table>
    </center></div><p><a href="class_book_begin041.htm">第一页</a> <a href="class_book_begin042.htm">第二页</a> <a href="class_book_begin043.htm">第三页</a> 
    第四页<br>
    <a href="class_book_begin045.htm">第五页</a> <a href="class_book_begin046.htm">第六页</a> 
    <a href="class_book_begin047.htm">第七页</a> <a href="../class_book.htm">返回</a> 
    &nbsp; <br>
    </p>
    <div align="center"><center><table border="0" cellpadding="8" cellspacing="0" width="100%">
      <tr>
        <td width="100%"><font size="3" color="#8000FF"><strong><em>第四章：按钮（4）</em></strong></font></td>
      </tr>
      <tr>
        <td width="100%" style="background-color: rgb(232,255,254)"><p ALIGN="JUSTIFY"><strong>先实现数据的输入，请看代码。</strong></p>
        <p ALIGN="JUSTIFY"><strong>与未创立组的控件相比，它的事件里多了Index参数，组里所有的对象都使用同一个事件。</strong></p>
        <p ALIGN="JUSTIFY"><strong>先在General里声明窗体级全局变量：</strong></p>
        <p ALIGN="JUSTIFY"><strong><font color="#004080">Dim Num1, Num2 As Single<br>
        Dim StrNum1, StrNum2 As String<br>
        Dim FirstNum As Boolean </font><font color="#008040">'判断是否是数字开头</font></strong></p>
        <p ALIGN="JUSTIFY"><strong>因为Text1里是存放字符串的，所以要把输入的数据进行运算，必须把字符型变量转变为实型变量，分别用Num1、Num2和StrNum1、StrNum2进行存放。</strong></p>
        <p ALIGN="JUSTIFY"><strong>在Form_Load事件里给变量初赋值：</strong></p>
        <p ALIGN="JUSTIFY"><font color="#004080"><strong>Num1 = 0<br>
        Num2 = 0<br>
        StrNum1 = &quot;&quot;<br>
        StrNum2 = &quot;&quot;<br>
        FirstNum = True</strong></font></p>
        <p ALIGN="JUSTIFY"><strong>因为17个按钮使用的是同一事件，所以我们用一个Select 
        Case语句区分各个按钮，双击任意按钮输入代码：</strong></p>
        <p ALIGN="JUSTIFY"><font color="#004080"><strong>Private Sub Command1_Click(Index As 
        Integer)</strong></font></p>
        <blockquote>
          <p ALIGN="JUSTIFY"><font color="#004080"><strong>Select Case Index</strong></font></p>
          <blockquote>
            <p ALIGN="JUSTIFY"><font color="#004080"><strong>Case 0 To 9</strong></font></p>
            <blockquote>
              <p ALIGN="JUSTIFY"><font color="#004080"><strong>If FirstNum Then</strong></font></p>
              <blockquote>
                <p ALIGN="JUSTIFY"><strong><font color="#004080">StrNum1 = Str(Index)</font><font color="#008040">’实型转字符型</font><br>
                <font color="#004080">FirstNum = False</font><font color="#008040">’初赋值为假</font></strong></p>
              </blockquote>
              <p ALIGN="JUSTIFY"><strong><font color="#004080">Else</font><font color="#008040">’非初赋值</font></strong></p>
              <blockquote>
                <p ALIGN="JUSTIFY"><font color="#004080"><strong>StrNum1 = StrNum1 + Str(Index)</strong></font></p>
              </blockquote>
              <p ALIGN="JUSTIFY"><font color="#004080"><strong>End If</strong></font></p>
              <p ALIGN="JUSTIFY"><strong><font color="#004080">Text1.Text = StrNum1</font><font color="#008040">’显示</font></strong></p>
            </blockquote>
            <p ALIGN="JUSTIFY"><font color="#FF0000"><strong>&lt;还有其他语句，等待插入&gt;</strong></font></p>
          </blockquote>
          <p ALIGN="JUSTIFY"><font color="#004080"><strong>End Select</strong></font></p>
        </blockquote>
        <p ALIGN="JUSTIFY"><font color="#004080"><strong>End Sub</strong></font></p>
        <p ALIGN="JUSTIFY"><strong>运行程序的话已经可以输入数据，下面我们来处理小数点。</strong></p>
        <p ALIGN="JUSTIFY"><strong>在General里声明新的变量：</strong></p>
        <p ALIGN="JUSTIFY"><strong><font color="#004080">Dim PointFlag As Boolean </font><font color="#008040">'判断是否已有小数点</font></strong></p>
        <p ALIGN="JUSTIFY"><strong>我们知道小数点只能输入一次，一个数据中不能有多个小数点存在，所以需要一个布尔变量做判断。</strong></p>
        <p ALIGN="JUSTIFY"><strong>在Form_Load里进行初赋值：</strong></p>
        <p ALIGN="JUSTIFY"><font color="#004080"><strong>PointFlag = False</strong></font></p>
        <p ALIGN="JUSTIFY"><strong>在Command的单击事件里接着上面输入新的代码：</strong></p>
        <blockquote>
          <p ALIGN="JUSTIFY"><font color="#004080"><strong>Case 10</strong></font></p>
          <blockquote>
            <p ALIGN="JUSTIFY"><strong><font color="#004080">If Not PointFlag Then</font><font color="#008040">’如果没有小数点</font></strong></p>
            <blockquote>
              <p ALIGN="JUSTIFY"><strong><font color="#004080">If FirstNum Then</font><font color="#008040">’如果是第一个字符</font></strong></p>
              <blockquote>
                <p ALIGN="JUSTIFY"><font color="#004080"><strong>StrNum1 = &quot;0.&quot;<br>
                FirstNum = False</strong></font></p>
              </blockquote>
              <p ALIGN="JUSTIFY"><font color="#004080"><strong>Else</strong></font></p>
              <blockquote>
                <p ALIGN="JUSTIFY"><font color="#004080"><strong>StrNum1 = StrNum1 + &quot;.&quot;</strong></font></p>
              </blockquote>
              <p ALIGN="JUSTIFY"><font color="#004080"><strong>End If</strong></font></p>
            </blockquote>
            <p ALIGN="JUSTIFY"><strong><font color="#004080">Else</font><font color="#008040">’已有小数点</font></strong></p>
            <blockquote>
              <p ALIGN="JUSTIFY"><strong><font color="#004080">Exit Sub</font><font color="#008040">’则退出单击事件</font></strong></p>
            </blockquote>
            <p ALIGN="JUSTIFY"><font color="#004080"><strong>End If</strong></font></p>
            <p ALIGN="JUSTIFY"><font color="#004080"><strong>PointFlag = True<br>
            Text1.Text = StrNum1</strong></font></p>
          </blockquote>
        </blockquote>
        </td>
      </tr>
    </table>
    </center></div><p align="right"><strong><a href="#top"><img src="top2.gif" border="0" WIDTH="27" HEIGHT="30"></a></strong></td>
  </tr>
</table>
</center></div>

<p>　</p>
</body>
</html>
<!--webbot bot="HTMLMarkup" TAG="XBOT" StartSpan --></SCRIPT><!--webbot BOT="HTMLMarkup" endspan -->

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -