|
|
工具版本兼容问题
基本数据类型
undefined，Boolean,Number,String，null
示例
1
:
声明了但未赋值
示例
2
:
布尔
示例
3
:
数字
示例
4
:
字符串
示例
5
:
动态类型
示例
6
:
变量类型判断
示例
7
:
空对象/对象不存在
当一个变量被声明了，却没有赋值的时候，叫做 undefined
");
window.frames["iframe_show1075"].document.write(decodeHtml($("textarea#stepcodeTextarea1075").val()));
window.frames["iframe_show1075"].document.close();
$(window.frames["iframe_show1075"]).load(function(){
$("#iframe_show1075").height($("#iframe_show1075").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1075").height($("#iframe_show1075").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var x; //声明了变量x,但是没有赋值
document.write('声明了，但是没有赋值的变量 x: '+x);
</script>
<script>
var x; //声明了变量x,但是没有赋值
document.write('声明了，但是没有赋值的变量 x: '+x);
</script>
");
window.frames["iframe1075"].document.write(decodeHtml(code1075));
window.frames["iframe1075"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1075"]).load(function(){
$("#iframe1075").height($("#iframe1075").contents().find("body").height()+showittryitheight);
});
$("#iframe1075").height($("#iframe1075").contents().find("body").height()+showittryitheight);
alreadyWriteCode1075 = code1075;
$("#rendering1075").hide();
$("#rendered1075").show();
}
var tRereshRetry2DemoPanel1075 = setInterval(rereshRetry2DemoPanel1075,1000);
var binded1075 = false;
$("textarea#stepcodeTextarea1075").keyup(function(){
if(!binded1075){
$(window).bind('beforeunload',function(){
binded1075 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1075 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1075!=newCode){
// window.frames["iframe1075"].document.write("
");
// window.frames["iframe1075"].document.write(decodeHtml($("textarea#stepcodeTextarea1075").val()));
// window.frames["iframe1075"].document.close();
// $(window.frames["iframe1075"]).load(function(){
// $("#iframe1075").height($("#iframe1075").contents().find("body").height()+showittryitheight);
// });
// code1075 = newCode;
// }
});
$(".tryButton1075").click(function(){
$("#tryDiv1075").show();
$("#stepcodeTextarea1075").focus();
$("#stepcodeTextarea1075").height(200);
$("#iframe1075").height(0);
window.frames["iframe1075"].document.write("
");
window.frames["iframe1075"].document.write(decodeHtml($("textarea#stepcodeTextarea1075").val()));
window.frames["iframe1075"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1075"]).load(function(){
$("#iframe1075").height($("#iframe1075").contents().find("body").height()+showittryitheight);
});
$("#iframe1075").height($("#iframe1075").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1075.focus();
editor1075.setSize(null, "250");
$("#rendering1075").hide();
$("#rendered1075").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1075 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1075"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1075.on("change",function(doc){
if(!binded1075){
$(window).bind('beforeunload',function(){
binded1075 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1075 = newCode;
$("textarea#stepcodeTextarea1075").val(newCode);
if(alreadyWriteCode1075!=code1075){
lastModifedTime1075 = new Date().getTime();
$("#rendering1075").show();
$("#rendered1075").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1075 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1075.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1075").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
Boolean变量有两种值，分别是true或者false
");
window.frames["iframe_show1076"].document.write(decodeHtml($("textarea#stepcodeTextarea1076").val()));
window.frames["iframe_show1076"].document.close();
$(window.frames["iframe_show1076"]).load(function(){
$("#iframe_show1076").height($("#iframe_show1076").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1076").height($("#iframe_show1076").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var x=true;
var y=false;
document.write("布尔值:"+x);
document.write("<br>");
document.write("布尔值:"+y);
</script>
<script>
var x=true;
var y=false;
document.write("布尔值:"+x);
document.write("<br>");
document.write("布尔值:"+y);
</script>
");
window.frames["iframe1076"].document.write(decodeHtml(code1076));
window.frames["iframe1076"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1076"]).load(function(){
$("#iframe1076").height($("#iframe1076").contents().find("body").height()+showittryitheight);
});
$("#iframe1076").height($("#iframe1076").contents().find("body").height()+showittryitheight);
alreadyWriteCode1076 = code1076;
$("#rendering1076").hide();
$("#rendered1076").show();
}
var tRereshRetry2DemoPanel1076 = setInterval(rereshRetry2DemoPanel1076,1000);
var binded1076 = false;
$("textarea#stepcodeTextarea1076").keyup(function(){
if(!binded1076){
$(window).bind('beforeunload',function(){
binded1076 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1076 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1076!=newCode){
// window.frames["iframe1076"].document.write("
");
// window.frames["iframe1076"].document.write(decodeHtml($("textarea#stepcodeTextarea1076").val()));
// window.frames["iframe1076"].document.close();
// $(window.frames["iframe1076"]).load(function(){
// $("#iframe1076").height($("#iframe1076").contents().find("body").height()+showittryitheight);
// });
// code1076 = newCode;
// }
});
$(".tryButton1076").click(function(){
$("#tryDiv1076").show();
$("#stepcodeTextarea1076").focus();
$("#stepcodeTextarea1076").height(200);
$("#iframe1076").height(0);
window.frames["iframe1076"].document.write("
");
window.frames["iframe1076"].document.write(decodeHtml($("textarea#stepcodeTextarea1076").val()));
window.frames["iframe1076"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1076"]).load(function(){
$("#iframe1076").height($("#iframe1076").contents().find("body").height()+showittryitheight);
});
$("#iframe1076").height($("#iframe1076").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1076.focus();
editor1076.setSize(null, "250");
$("#rendering1076").hide();
$("#rendered1076").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1076 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1076"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1076.on("change",function(doc){
if(!binded1076){
$(window).bind('beforeunload',function(){
binded1076 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1076 = newCode;
$("textarea#stepcodeTextarea1076").val(newCode);
if(alreadyWriteCode1076!=code1076){
lastModifedTime1076 = new Date().getTime();
$("#rendering1076").show();
$("#rendered1076").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1076 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1076.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1076").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
javascript中的Number可以表示十进制，八进制，十六进制整数，浮点数，科学记数法
");
window.frames["iframe_show1077"].document.write(decodeHtml($("textarea#stepcodeTextarea1077").val()));
window.frames["iframe_show1077"].document.close();
$(window.frames["iframe_show1077"]).load(function(){
$("#iframe_show1077").height($("#iframe_show1077").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1077").height($("#iframe_show1077").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var a=10; //十进制
var b=012;//第一位是0，表示八进制
var c=0xA;//0x开头表示十六进制
var d=3.14;//有小数点表示浮点数
var e=3.14e2;//使用e的幂表示科学计数法
document.write("十进制 10 的值: "+a);
document.write("<br>");
document.write("八进制 012 的值: "+b);
document.write("<br>");
document.write("十六进制 0xA 的值: "+c);
document.write("<br>");
document.write("浮点数 3.14 的值: "+d);
document.write("<br>");
document.write("科学记数法 3.14e2 的值: "+e);
document.write("<br>");
</script>
<script>
var a=10; //十进制
var b=012;//第一位是0，表示八进制
var c=0xA;//0x开头表示十六进制
var d=3.14;//有小数点表示浮点数
var e=3.14e2;//使用e的幂表示科学计数法
document.write("十进制 10 的值: "+a);
document.write("<br>");
document.write("八进制 012 的值: "+b);
document.write("<br>");
document.write("十六进制 0xA 的值: "+c);
document.write("<br>");
document.write("浮点数 3.14 的值: "+d);
document.write("<br>");
document.write("科学记数法 3.14e2 的值: "+e);
document.write("<br>");
</script>
");
window.frames["iframe1077"].document.write(decodeHtml(code1077));
window.frames["iframe1077"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1077"]).load(function(){
$("#iframe1077").height($("#iframe1077").contents().find("body").height()+showittryitheight);
});
$("#iframe1077").height($("#iframe1077").contents().find("body").height()+showittryitheight);
alreadyWriteCode1077 = code1077;
$("#rendering1077").hide();
$("#rendered1077").show();
}
var tRereshRetry2DemoPanel1077 = setInterval(rereshRetry2DemoPanel1077,1000);
var binded1077 = false;
$("textarea#stepcodeTextarea1077").keyup(function(){
if(!binded1077){
$(window).bind('beforeunload',function(){
binded1077 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1077 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1077!=newCode){
// window.frames["iframe1077"].document.write("
");
// window.frames["iframe1077"].document.write(decodeHtml($("textarea#stepcodeTextarea1077").val()));
// window.frames["iframe1077"].document.close();
// $(window.frames["iframe1077"]).load(function(){
// $("#iframe1077").height($("#iframe1077").contents().find("body").height()+showittryitheight);
// });
// code1077 = newCode;
// }
});
$(".tryButton1077").click(function(){
$("#tryDiv1077").show();
$("#stepcodeTextarea1077").focus();
$("#stepcodeTextarea1077").height(200);
$("#iframe1077").height(0);
window.frames["iframe1077"].document.write("
");
window.frames["iframe1077"].document.write(decodeHtml($("textarea#stepcodeTextarea1077").val()));
window.frames["iframe1077"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1077"]).load(function(){
$("#iframe1077").height($("#iframe1077").contents().find("body").height()+showittryitheight);
});
$("#iframe1077").height($("#iframe1077").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1077.focus();
editor1077.setSize(null, "250");
$("#rendering1077").hide();
$("#rendered1077").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1077 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1077"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1077.on("change",function(doc){
if(!binded1077){
$(window).bind('beforeunload',function(){
binded1077 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1077 = newCode;
$("textarea#stepcodeTextarea1077").val(newCode);
if(alreadyWriteCode1077!=code1077){
lastModifedTime1077 = new Date().getTime();
$("#rendering1077").show();
$("#rendered1077").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1077 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1077.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1077").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
与java不同的是，javascript中没有字符的概念，只有字符串，所以单引号和双引号，都用来表示字符串。
");
window.frames["iframe_show1078"].document.write(decodeHtml($("textarea#stepcodeTextarea1078").val()));
window.frames["iframe_show1078"].document.close();
$(window.frames["iframe_show1078"]).load(function(){
$("#iframe_show1078").height($("#iframe_show1078").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1078").height($("#iframe_show1078").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var x='hello '; //单引号
var y="javascript"; //双引号
document.write("单引号的字符串:"+x);
document.write("<br>");
document.write("双引号的字符串:"+y);
</script>
<script>
var x='hello '; //单引号
var y="javascript"; //双引号
document.write("单引号的字符串:"+x);
document.write("<br>");
document.write("双引号的字符串:"+y);
</script>
");
window.frames["iframe1078"].document.write(decodeHtml(code1078));
window.frames["iframe1078"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1078"]).load(function(){
$("#iframe1078").height($("#iframe1078").contents().find("body").height()+showittryitheight);
});
$("#iframe1078").height($("#iframe1078").contents().find("body").height()+showittryitheight);
alreadyWriteCode1078 = code1078;
$("#rendering1078").hide();
$("#rendered1078").show();
}
var tRereshRetry2DemoPanel1078 = setInterval(rereshRetry2DemoPanel1078,1000);
var binded1078 = false;
$("textarea#stepcodeTextarea1078").keyup(function(){
if(!binded1078){
$(window).bind('beforeunload',function(){
binded1078 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1078 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1078!=newCode){
// window.frames["iframe1078"].document.write("
");
// window.frames["iframe1078"].document.write(decodeHtml($("textarea#stepcodeTextarea1078").val()));
// window.frames["iframe1078"].document.close();
// $(window.frames["iframe1078"]).load(function(){
// $("#iframe1078").height($("#iframe1078").contents().find("body").height()+showittryitheight);
// });
// code1078 = newCode;
// }
});
$(".tryButton1078").click(function(){
$("#tryDiv1078").show();
$("#stepcodeTextarea1078").focus();
$("#stepcodeTextarea1078").height(200);
$("#iframe1078").height(0);
window.frames["iframe1078"].document.write("
");
window.frames["iframe1078"].document.write(decodeHtml($("textarea#stepcodeTextarea1078").val()));
window.frames["iframe1078"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1078"]).load(function(){
$("#iframe1078").height($("#iframe1078").contents().find("body").height()+showittryitheight);
});
$("#iframe1078").height($("#iframe1078").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1078.focus();
editor1078.setSize(null, "250");
$("#rendering1078").hide();
$("#rendered1078").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1078 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1078"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1078.on("change",function(doc){
if(!binded1078){
$(window).bind('beforeunload',function(){
binded1078 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1078 = newCode;
$("textarea#stepcodeTextarea1078").val(newCode);
if(alreadyWriteCode1078!=code1078){
lastModifedTime1078 = new Date().getTime();
$("#rendering1078").show();
$("#rendered1078").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1078 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1078.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1078").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
变量的类型是动态的，当值是整数的时候，就是Number类型，当值是字符串的时候，就是String类型
");
window.frames["iframe_show1079"].document.write(decodeHtml($("textarea#stepcodeTextarea1079").val()));
window.frames["iframe_show1079"].document.close();
$(window.frames["iframe_show1079"]).load(function(){
$("#iframe_show1079").height($("#iframe_show1079").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1079").height($("#iframe_show1079").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var x=10; //Number类型
document.write("此时 x的值是 "+x+" 类型是数字");
document.write("<br>");
x = "hello javascript"; //String类型
document.write("此时 x的值是 "+x+" 类型是字符串");
</script>
<script>
var x=10; //Number类型
document.write("此时 x的值是 "+x+" 类型是数字");
document.write("<br>");
x = "hello javascript"; //String类型
document.write("此时 x的值是 "+x+" 类型是字符串");
</script>
");
window.frames["iframe1079"].document.write(decodeHtml(code1079));
window.frames["iframe1079"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1079"]).load(function(){
$("#iframe1079").height($("#iframe1079").contents().find("body").height()+showittryitheight);
});
$("#iframe1079").height($("#iframe1079").contents().find("body").height()+showittryitheight);
alreadyWriteCode1079 = code1079;
$("#rendering1079").hide();
$("#rendered1079").show();
}
var tRereshRetry2DemoPanel1079 = setInterval(rereshRetry2DemoPanel1079,1000);
var binded1079 = false;
$("textarea#stepcodeTextarea1079").keyup(function(){
if(!binded1079){
$(window).bind('beforeunload',function(){
binded1079 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1079 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1079!=newCode){
// window.frames["iframe1079"].document.write("
");
// window.frames["iframe1079"].document.write(decodeHtml($("textarea#stepcodeTextarea1079").val()));
// window.frames["iframe1079"].document.close();
// $(window.frames["iframe1079"]).load(function(){
// $("#iframe1079").height($("#iframe1079").contents().find("body").height()+showittryitheight);
// });
// code1079 = newCode;
// }
});
$(".tryButton1079").click(function(){
$("#tryDiv1079").show();
$("#stepcodeTextarea1079").focus();
$("#stepcodeTextarea1079").height(200);
$("#iframe1079").height(0);
window.frames["iframe1079"].document.write("
");
window.frames["iframe1079"].document.write(decodeHtml($("textarea#stepcodeTextarea1079").val()));
window.frames["iframe1079"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1079"]).load(function(){
$("#iframe1079").height($("#iframe1079").contents().find("body").height()+showittryitheight);
});
$("#iframe1079").height($("#iframe1079").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1079.focus();
editor1079.setSize(null, "250");
$("#rendering1079").hide();
$("#rendered1079").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1079 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1079"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1079.on("change",function(doc){
if(!binded1079){
$(window).bind('beforeunload',function(){
binded1079 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1079 = newCode;
$("textarea#stepcodeTextarea1079").val(newCode);
if(alreadyWriteCode1079!=code1079){
lastModifedTime1079 = new Date().getTime();
$("#rendering1079").show();
$("#rendered1079").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1079 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1079.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1079").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
使用typeof来进行判断数据类型
正是因为变量是动态类型的，所以无法确定当前到底是哪种类型，这个时候，就可以使用typeof来进行判断
");
window.frames["iframe_show1080"].document.write(decodeHtml($("textarea#stepcodeTextarea1080").val()));
window.frames["iframe_show1080"].document.close();
$(window.frames["iframe_show1080"]).load(function(){
$("#iframe_show1080").height($("#iframe_show1080").contents().find("body").height()+showittryitheight);
});
$("#iframe_show1080").height($("#iframe_show1080").contents().find("body").height()+showittryitheight);
setTimeout(function(){
},500);
});
<script>
var x;
document.write('声明了但是未赋值的时候，类型是： '+typeof x);
document.write("<br>");
x=5;
document.write('赋值为5之后，类型是： '+typeof x);
document.write("<br>");
x=5.1;
document.write('赋值为5.1之后，类型是： '+typeof x);
document.write("<br>");
x=true;
document.write('赋值为true之后，类型是： '+typeof x);
document.write("<br>");
x="hello";
document.write('赋值为hello之后，类型是： '+typeof x);
</script>
<script>
var x;
document.write('声明了但是未赋值的时候，类型是： '+typeof x);
document.write("<br>");
x=5;
document.write('赋值为5之后，类型是： '+typeof x);
document.write("<br>");
x=5.1;
document.write('赋值为5.1之后，类型是： '+typeof x);
document.write("<br>");
x=true;
document.write('赋值为true之后，类型是： '+typeof x);
document.write("<br>");
x="hello";
document.write('赋值为hello之后，类型是： '+typeof x);
</script>
");
window.frames["iframe1080"].document.write(decodeHtml(code1080));
window.frames["iframe1080"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1080"]).load(function(){
$("#iframe1080").height($("#iframe1080").contents().find("body").height()+showittryitheight);
});
$("#iframe1080").height($("#iframe1080").contents().find("body").height()+showittryitheight);
alreadyWriteCode1080 = code1080;
$("#rendering1080").hide();
$("#rendered1080").show();
}
var tRereshRetry2DemoPanel1080 = setInterval(rereshRetry2DemoPanel1080,1000);
var binded1080 = false;
$("textarea#stepcodeTextarea1080").keyup(function(){
if(!binded1080){
$(window).bind('beforeunload',function(){
binded1080 = true;
return "xxxx";
});
}
var newCode = $(this).val()
code1080 = newCode;
/*below code is replaced by function rereshRetry2DemoPanel()*/
// if(code1080!=newCode){
// window.frames["iframe1080"].document.write("
");
// window.frames["iframe1080"].document.write(decodeHtml($("textarea#stepcodeTextarea1080").val()));
// window.frames["iframe1080"].document.close();
// $(window.frames["iframe1080"]).load(function(){
// $("#iframe1080").height($("#iframe1080").contents().find("body").height()+showittryitheight);
// });
// code1080 = newCode;
// }
});
$(".tryButton1080").click(function(){
$("#tryDiv1080").show();
$("#stepcodeTextarea1080").focus();
$("#stepcodeTextarea1080").height(200);
$("#iframe1080").height(0);
window.frames["iframe1080"].document.write("
");
window.frames["iframe1080"].document.write(decodeHtml($("textarea#stepcodeTextarea1080").val()));
window.frames["iframe1080"].document.close();
//load和下面的非load必需并存，因为如果代码用到了jquery就必须使用load的方式
$(window.frames["iframe1080"]).load(function(){
$("#iframe1080").height($("#iframe1080").contents().find("body").height()+showittryitheight);
});
$("#iframe1080").height($("#iframe1080").contents().find("body").height()+showittryitheight);
this.scrollIntoView(true);
editor1080.focus();
editor1080.setSize(null, "250");
$("#rendering1080").hide();
$("#rendered1080").hide();
});
var mixedMode = {
name: "htmlmixed",
scriptTypes: [{matches: /\/x-handlebars-template|\/x-mustache/i,
mode: null},
{matches: /(text|application)\/(x-)?vb(a|script)/i,
mode: "vbscript"}]
};
var editor1080 = CodeMirror.fromTextArea(document.getElementById("stepcodeTextarea1080"), {
lineNumbers: true,
styleActiveLine: true,
matchBrackets: true,
mode:"text/html",
theme:"eclipse",
selectionPointer: true,
lineWrapping: true,
extraKeys: {
"Alt-/": "autocomplete",
"Ctrl-F": "findPersistent",
"F8": function(cm) {
cm.setOption("fullScreen", !cm.getOption("fullScreen"));
},
"Esc": function(cm) {
if (cm.getOption("fullScreen")) cm.setOption("fullScreen", false);
}
}
});
editor1080.on("change",function(doc){
if(!binded1080){
$(window).bind('beforeunload',function(){
binded1080 = true;
return "xxxx";
});
}
var newCode = doc.getValue();
code1080 = newCode;
$("textarea#stepcodeTextarea1080").val(newCode);
if(alreadyWriteCode1080!=code1080){
lastModifedTime1080 = new Date().getTime();
$("#rendering1080").show();
$("#rendered1080").hide();
}
// alert(doc.getValue());
});
$(".CodeMirror").addClass("form-control");
// var editor1080 = CodeMirror.fromTextArea(, {
// lineNumbers: true,
// styleActiveLine: true,
// matchBrackets: true,
// theme:"eclipse",
// });
editor1080.on("change",function(doc){
// alert(doc.getValue());
});
$("#tryDiv1080").hide();
});
$("div.codemirrorTips span").addClass("glyphicon glyphicon-asterisk");
1. 双击选中单词
2. 三击选中整行
3. CTRL+F 查找
4. F8 全屏编辑，再次点击恢复
|
|
渲染中
渲染完成
|
代码高亮插件双击即可选中，不过部分同学反应，通过代码高亮插件复制的代码无法在IDEA里正常显示，这里提供TEXTAREA的方式，方便复制，谢谢
1. 自行完成练习
根据练习目标尽量自己实现代码效果，期间会碰到疑问，难题，和自己不懂的地方，这些都是必要的过程
2. 带着疑问查看答案
完成过程中，碰到无法解决的问题，带着疑问，查看答案，分析答案的解决思路
3. 查看答案讲解视频
依然有不明白的地方，点开视频讲解，带着疑问，听视频讲解有问题的部分
4. 再做一遍
理解后，再从头做一遍，把有疑问的地方都捋清楚
5. 总结
最后再总结一遍，总结思路，总结解决办法，以后遇到类似的问题，怎么处理
HOW2J公众号，关注后实时获知布最新的教程和优惠活动，谢谢。
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