js小于等于怎么写 js小于等于号怎么打

html:

(4)bold函数：使字体加粗，与...标签结果相同。script:

$('#3').attr("id");//获取id 然后再判断大小

用JS脚本如何实现多关键+多条件的查询(SQL语句)?

朋友，脚本语言是一种简单的语言，是没有办法实现这样的功能的，不管是JS or VBS。只有asp、php、jsp程序语言可以。

```

Array.prototype._killSpaceFun = function(res){return res.replace(/s/g,"");}

Array.prototype._whereFun = function(row,conditions){

var fs = [];

conditions.forEach(function(,index){

var key = .key;

var val = .value;

var type = .type;

var = false;

var v = row[key];

if(typeof v != "undefined"){

switch(type){

case "==":

= (v == val);

case "!=":

= (v != val);

= (String(v).toLowerCase().indexOf(String(val)) >= 0);

case "!%":

= (String(v).toLowerCase().indexOf(String(val)) < 0);

case "#%":

= (String(v).substr(0,String(val).length) == String(val));

case ">":

= (Number(v) > Number(val));

case ">=":

= (Number(v) >= Number(val));

case "<":

= (Number(v) < Number(val));

case "<=":

= (Number(v) <= Number(val));

default:

=false;

}fs.push();

}});

return !fs.includes(false);

}Array.prototype._formatFun = function(cond){

var cl = [];

var ret = null;

cc.forEach(function(,index){

if(ret == null){

if(cond.indexOf()>=0){

var = cond.split();

ret = {"key":[0]};

ret.type = ;

if(ret.value == null){ret=null;}

})

return ret;

};

Array.prototype.Select = function(fields,where,igCase){

igCase = typeof igCase == "undefined" ? true : Boolean(igCase);

where = typeof where == "undefined" ? "" : String(where);

where = igCase == true ? where.toLowerCase() : where;

fields = this._killSpaceFun(fields);

var flds = igCase == true ? this._killSpaceFun(fields).toLowerCase().split(",") : this._killSpaceFun(fields).split(",");

var obj_conds = [];

src_conds.forEach(function(,index){

var cond = obj_conds._formatFun();

if(cond!=null){

obj_conds.push(cond);

}});

var _ls = [];

this.forEach(function(,index){

if(obj_conds._whereFun(,obj_conds)){

if(fields == "" || fields == ""){

_ls.push();

var _row = {};

flds.forEach(function(key,idx){

_row[key] = typeof [key] == "undefined" ? null : [key];

_ls.push(_row);

return _ls;

}```

试下这个，无聊的时候测试的产物。

使用如下

```

var list = [{id:1,"name":"}return i;a"},{id:2,"name":"aa"},{id:3,"name":"bbb"}];

//查询基本语法,array.Select("字段列表","条件")

//==:等于

//>=:大于等于

//<=:小于等于

//%%:%A%

//#%:A%

//%#:%A

//!=:不等于

//>:大于

//<:小于

list.Select("id,name","id > 1");

```

js如何判断用户输入表单的值大于等于500时显示1，小于500时显示2并且隐藏表格一行

var value = $("input").val();

if(value>=500)

{$("#image2").hide();

$("#image1").show();

}else

{$("#image1").hide();

(3)rrse函数：将数组元素顺序颠倒。$("#image2"$符号表示字符串的结束).show();

$("tr:last").hide();

}大概这样？