Flex StringUtil 工具类 字符串函数

转自：http://www.cnblogs.com/god_bless_you/archive/2011/07/29/2121145.html

 

最近发现Flex处理字符串的工具类一共有三个，分别是：

1. mx.utils包下的StringUtil
2. mx.utils包下的RPCStringUtil
3. as3corelib类库下的StringUtil

下面分别整理及介绍下这三个工具类的用法：

mx.utils包下的StringUtil

1.trim()

2.isWhitespace()   判断是否是空白字符

3.trimArrayElements()

删除数组中每个元素的开头和末尾的所有空格字符，此处数组作为字符串存储。

4.substitute()

使用传入的各个参数替换指定的字符串内的“{n}”标记。

示例：

var str:String = "here is some info '{0}' and {1}
"; 

trace(StringUtil.substitute(str, 15.4, true
)); 

// this will output the following string: 


// "here is some info '15.4' and true" 

5.repeat()

Returns a string consisting of a specified string concatenated with itself a specified number of times.

大部分SDK中无此函数，看其源码是用字符串相加实现的，不推荐使用。

6.restrict（）

 /**
  *  Removes "unallowed" characters from a string.
  *  A "restriction string" such as <code>"A-Z0-9"</code>
  *  is used to specify which characters are allowed.
  *  This method uses the same logic as the <code>restrict</code>
  *  property of TextField.
  *
  *  @param str The input string.
  *
  *  @param restrict The restriction string.
  *
  *  @result The input string, minus any characters
  *  that are not allowed by the restriction string.
  *  
  */

同上，大部分SDK中无此函数

mx.utils包下的RPCStringUtil

mx.utils下包StringUtil的子集，用法同StringUtil

as3corelib类库下的StringUtil

1. stringsAreEqual()    判断字符串是否相等
2. trim()    去除首尾的空白字符
3. ltrim()   去除首部的空白字符
4. rtrim()   去除尾部的空白字符
5. beginsWith()   判断字符串是否已该前缀开头
6. endsWith()    判断字符串是否已该后缀结尾
7. remove()    去除字符串中的部分字符
8. replace()   替换字符串中的部分字符
9. stringHasValue()  判断字符串是否有值

代码示例：

<?xml version="1.0
" encoding="utf-8
"?>
<mx:Application 
	xmlns:mx="http://www.adobe.com/2006/mxml
" 
	backgroundColor="#ffffff
"
	layout="absolute
">
	<mx:Script>
		<![CDATA[
			import com.adobe.utils.StringUtil;
		]]>
	</mx:Script>
	<mx:VBox>
		<mx:HBox>
			<mx:Label text="input1
"/>		
			<mx:TextInput id="input1
" text="input1
"/>
		</mx:HBox>
		<mx:HRule width="100%
" height="1
"/>	
		<mx:HBox>
			<mx:Label text="is input1 begins with:
"/>		
			<mx:TextInput id="beginsWith
" text="i
"/>
		</mx:HBox>	
		<mx:HRule width="100%
" height="1
"/>	
		<mx:Text text="beginsWith:{ StringUtil.beginsWith(input1.text,beginsWith.text)}
"/>
		<mx:HRule width="100%
" height="1
"/>
		<mx:Text text="input1 has value ?:{ StringUtil.stringHasValue(input1.text) }
"/>
		<mx:HRule width="100%
" height="1
"/>
		<mx:HBox>
			<mx:Label text="is input1 ends with:
"/>		
			<mx:TextInput id="endsWith
" text="1
"/>
		</mx:HBox>
		<mx:Text text="endsWith:{ StringUtil.endsWith(input1.text,endsWith.text)}
"/>			
		<mx:HRule width="100%
" height="1
"/>
		<mx:HBox>
			<mx:Label text="string to be removed from input1
"/>		
			<mx:TextInput id="removeString
"/>
		</mx:HBox>
		<mx:Text text="remove:{ StringUtil.remove(input1.text,removeString.text)}
"/>
		<mx:HRule width="100%
" height="1
"/>
		<mx:HBox>
			<mx:Label text="string to be replaced from input1
"/>		
			<mx:TextInput id="replace
"/>
		</mx:HBox>
		<mx:HBox>
			<mx:Label text="string to be replace with
"/>		
			<mx:TextInput id="replaceWith
"/>
		</mx:HBox>			
		<mx:Text text="replace:{ StringUtil.replace(input1.text,replace.text,replaceWith.text) }
"/>
		<mx:HRule width="100%
" height="1
"/>
		<mx:Text text="ltrim:{ StringUtil.ltrim(input1.text)}
"/>
		<mx:Text text="trim:{StringUtil.trim(input1.text)}
"/>
		<mx:Text text="rtrim:{StringUtil.rtrim(input1.text)}
"/>
		<mx:HRule width="100%
" height="1
"/>
		<mx:HBox>
			<mx:Label text="input2
"/>		
			<mx:TextInput id="input2
" text="input1
"/>
			<mx:Label text="is case sensitive?
"/><mx:CheckBox id="caseSensitive
" selected="true
"/>
		</mx:HBox>
		<mx:Text text="input1 and input2 are equal?:{ StringUtil.stringsAreEqual(input1.text,input2.text,caseSensitive.selected)}
"/>
	</mx:VBox>
</mx:Application>