js 之 String工具类

 

String.prototype.replaceAll = function(AFindText, ARepText){
	raRegExp = new RegExp(AFindText, "g");
	return this.replace(raRegExp, ARepText);
}

//trim方法
String.prototype.trim = function(){
	return this.replace(/(^\s*)|(\s*$)/g, '');
}
//自定义统计字符数，一个中文算2个字符
String.prototype.mylength = function(){
	var arr = this.match(/[\u00FF-\uFFFF]/gi);
	if (!arr || arr == null) 
		return this.length;
	var len = this.length + arr.length;
	return len;
}

//自定义截取字符串（首位各取一半做限制）
String.prototype.mysubstring = function(limit){
	if (this.mylength() <= limit) {
		return this;
	}
	var len1 = 0;
	var len2 = 0;
	var arr1 = [];
	var arr2 = [];
	for (var i = 0; i < this.length; i++) {
		var it = this.substring(i, i + 1);
		len1 += it.mylength();
		if (len1 > limit / 2) 
			break;
		arr1[arr1.length] = it;
	}
	for (var i = 0; i < this.length; i++) {
		var it = this.substring(this.length - (i + 1), this.length - i);
		len2 += it.mylength();
		if (len2 > limit / 2) 
			break;
		arr2[arr2.length] = it;
	}
	var result = arr1.join('') + '...' + arr2.reverse().join('');
	return result;
}

//自定义截取字符串2（取前limit位）
String.prototype.mysubstring2 = function(limit){
	var len = 0;
	var arr = [];
	for (var i = 0; i < this.length; i++) {
		var it = this.substring(i, i + 1);
		len += it.mylength();
		if (len > limit) {
			break;
		}
		arr[arr.length] = it;
	}
	
	var result = arr.join("");
	return result;
}

//截取字符串(字符计算)
String.prototype.subStr = function(limit){
	var strTitleLimit = this;
	if (strTitleLimit.length > limit) {
		strTitleLimit = strTitleLimit.substring(0, limit - 1) + '...';
	}
	return strTitleLimit;
}