String.prototype.startsWith = function (startStr) { var d = startStr.length; return (d >= 0 && this.indexOf(startStr) == 0) }
String.prototype.endsWith = function (endStr) { var d = this.length – endStr.length; return (d >= 0 && this.lastIndexOf(endStr) == d) }
String.prototype.LTrim = function()
{
return this.replace(/(^s*)/g, “”);
}
String.prototype.Rtrim = function()
{
return this.replace(/(s*$)/g, “”);
}
String.prototype.Trim = function()
{
return this.replace(/(^s*)|(s*$)/g, “”);
}
String.prototype.Left = function(len)
{
if(isNaN(len)||len==null)
{
len = this.length;
}
else
{
if(parseInt(len)<0||parseInt(len)>this.length)
{
len = this.length;
}
}
return this.substr(0,len);
}
String.prototype.Right = function(len)
{
if(isNaN(len)||len==null)
{
len = this.length;
}
转载于:https://www.cnblogs.com/ziranquliu/p/5114058.html
发布者：全栈程序员-站长，转载请注明出处：https://javaforall.net/109181.html原文链接：https://javaforall.net
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